diff --git a/.Rbuildignore b/.Rbuildignore
index 01aa829..f28f38b 100644
--- a/.Rbuildignore
+++ b/.Rbuildignore
@@ -19,3 +19,4 @@
 ^zonebuilder-paper_files$
 ^vignettes/josis*$
 ^\.ccache$
+^CRAN-SUBMISSION$
diff --git a/DESCRIPTION b/DESCRIPTION
index b70c48e..9481212 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: zonebuilder
 Title: Create and Explore Geographic Zoning Systems
-Version: 0.0.2.9001
+Version: 0.1.0
 Authors@R: 
     c(person(given = "Robin",
              family = "Lovelace",
@@ -13,6 +13,8 @@ Authors@R:
              email = "mtennekes@gmail.com"))
 Description: Functions, documentation and example data to help divide
     geographic space into discrete polygons (zones).
+    The package supports new zoning systems that are documented in the
+    accompanying paper <doi:10.5311/JOSIS.2022.24.172>.
     The functions are motivated by research into the merits of different zoning systems
     <doi:10.1068/a090169>. A flexible 'ClockBoard' zoning system is
     provided, which breaks-up space by concentric rings
@@ -39,7 +41,6 @@ Suggests:
     rmarkdown,
     tmap,
     tmaptools,
-    pct,
     dplyr,
     lwgeom,
     leaflet,
@@ -50,4 +51,4 @@ VignetteBuilder:
 URL: https://github.com/zonebuilders/zonebuilder, https://zonebuilders.github.io/zonebuilder/
 Encoding: UTF-8
 LazyData: true
-RoxygenNote: 7.1.1
+RoxygenNote: 7.3.2
diff --git a/NAMESPACE b/NAMESPACE
index 007a7b5..4cb52af 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -1,5 +1,7 @@
 # Generated by roxygen2: do not edit by hand
 
+S3method(geo_select_aeq,sf)
+S3method(geo_select_aeq,sfc)
 export(london_a)
 export(london_c)
 export(zb_color)
@@ -8,7 +10,6 @@ export(zb_lines)
 export(zb_plot)
 export(zb_quadrat)
 export(zb_segment)
-export(zb_view)
 export(zb_zone)
 import(sf)
 importFrom(RColorBrewer,brewer.pal)
diff --git a/NEWS.md b/NEWS.md
index 2340cda..ff8117e 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,4 +1,8 @@
-# zonebuilder (development version)
+# zonebuilder 0.1.0 (2025-02)
+
+* Various issues fixed for CRAN (#36)
+* Removal of `zb_view()` function
+* Addition of citation to documentation
 
 # zonebuilder 0.0.2
 
diff --git a/R/from_stplanr.R b/R/from_stplanr.R
index b7ae70c..d513797 100644
--- a/R/from_stplanr.R
+++ b/R/from_stplanr.R
@@ -1,3 +1,12 @@
+#' Azimuthal Equidistant Projection
+#'
+#' @title Azimuthal Equidistant Projection
+#' @name geo_select_aeq
+#' @description Returns a CRS string for an Azimuthal Equidistant projection centered on the midpoint of an sf object's coordinates.
+#'
+#' @param shp An sf object.
+#' @return A CRS string for an Azimuthal Equidistant projection.
+#' @export
 geo_select_aeq.sf = function (shp) {
   #cent <- sf::st_geometry(shp)
   coords <- sf::st_coordinates(shp)
@@ -8,7 +17,8 @@ geo_select_aeq.sf = function (shp) {
   sf::st_crs(aeqd)
 }
 
-
+#' @rdname geo_select_aeq
+#' @export
 geo_select_aeq.sfc = function (shp) {
   #cent <- sf::st_geometry(shp)
   coords <- sf::st_coordinates(shp)
@@ -19,6 +29,7 @@ geo_select_aeq.sfc = function (shp) {
   sf::st_crs(aeqd)
 }
 
+#' @rdname geo_select_aeq
 geo_select_aeq = function (shp) {
   UseMethod("geo_select_aeq")
 }
@@ -26,5 +37,5 @@ geo_select_aeq = function (shp) {
 
 geo_project = function(shp) {
   crs = geo_select_aeq(shp)
-  st_transform(shp, crs = crs)
+  sf::st_transform(shp, crs = crs)
 }
diff --git a/R/plot.R b/R/plot.R
index e561207..e19d660 100644
--- a/R/plot.R
+++ b/R/plot.R
@@ -35,55 +35,6 @@ zb_color = function(z, palette = c("rings", "hcl", "dartboard")) {
   }
 }
 
-
-
-#' View zones
-#' 
-#' This function opens an interactive map of the zones
-#' 
-#' @param z An `sf` object containing zones covering the region
-#' @param alpha Alpha transparency, number between 0 (fully transparent) and 1 (not transparent)
-#' @param palette Palette type, one of \code{"hcl"} (a palette based on the HCL color space), \code{"rings"} (a palette which colors the rings using the YlOrBr color brewer palette), \code{"dartboard"} (a palette which resembles a dartboard)
-#' @param title The title of the plot
-#' @return An interactive map created with `tmap`
-#' @export
-#' @examples
-#' \donttest{
-#' z = zb_zone(london_c(), london_a())
-#' zb_view(z, palette = "rings")
-#' }
-zb_view = function(z, alpha = 0.4, palette = c("rings", "hcl", "dartboard"), title  = NULL) {
-  palette = match.arg(palette)
-  if (requireNamespace("tmap")) {
-    suppressMessages(tmap::tmap_mode("view"))
-    tmap::tmap_options(show.messages = FALSE)
-
-    cent = sf::st_set_crs(sf::st_set_geometry(z, "centroid"), sf::st_crs(z))
-    check_and_fix = tmap::tmap_options()$check.and.fix
-    if(!check_and_fix) {
-      message("Updating tmap settings with:\ntmap::tmap_options(check.and.fix = TRUE)")
-      tmap::tmap_options(check.and.fix = TRUE)
-    }
-    
-    z$color = zb_color(z, palette)
-    tm = tmap::tm_basemap("OpenStreetMap") +
-    tmap::tm_shape(z) + 
-      tmap::tm_fill("color", alpha = alpha, id = "label", group = "colors", popup.vars = c("circle_id", "segment_id", "label")) + 
-      tmap::tm_borders(group = "Borders", col = "black", lwd = 1.5) +
-    tmap::tm_shape(cent) +
-      tmap::tm_text("label", col = "black", size = "circle_id", group = "Labels") +
-      tmap::tm_scale_bar()
-    
-    if (!is.null(title)) {
-      tm + tmap::tm_layout(title = title)
-    } else {
-      tm
-    }
-  } else {
-    stop("Please install tmap")
-  }
-}
-
 #' Plot zones
 #' 
 #' This function opens a static map of the zones
@@ -113,7 +64,7 @@ zb_plot = function(z, palette = c("rings", "hcl", "dartboard"), title = NULL, te
   on.exit(par(oldpar)) # code line i + 1
   p = graphics::par(mar=c(.2,.2,.2,.2))
   plot(sf::st_geometry(z), col = z$color, border = "grey40")
-  co = st_coordinates(cent[sel,])
+  co = sf::st_coordinates(cent[sel,])
   mx = max(z$circle_id[sel])
   cex = seq(text_size[1], text_size[2], length.out = 9)[pmin(9, z$circle_id[sel] + (9-mx))]
   text(co[, 1], co[, 2], cex = cex, labels = z$label[sel])
diff --git a/R/zone.R b/R/zone.R
index fa08713..06ae143 100644
--- a/R/zone.R
+++ b/R/zone.R
@@ -28,20 +28,9 @@
 #' @examples
 #' # default settings
 #' z = zb_zone(london_c(), london_a())
-#' \donttest{
-#' zb_plot(z)
-#' if (require(tmap)) {
-#'   zb_view(z)
-#'   
-#'   z = zb_zone("Berlin")
-#'   zb_view(z)
-#'}
-#' 
-#' # variations
 #' zb_plot(zb_zone(london_c(), london_a(), n_circles = 2))
 #' zb_plot(zb_zone(london_c(), london_a(), n_circles = 4, distance = 2, distance_growth = 0))
 #' zb_plot(zb_zone(london_c(), london_a(), n_circles = 3, n_segments = c(1,4,8)))
-#' }
 zb_zone = function(x = NULL,
                    area = NULL,
                    n_circles = NA,
diff --git a/README.Rmd b/README.Rmd
index d7de897..c600e17 100644
--- a/README.Rmd
+++ b/README.Rmd
@@ -24,11 +24,11 @@ knitr::opts_chunk$set(
 [![CRAN status](https://www.r-pkg.org/badges/version/zonebuilder)](https://CRAN.R-project.org/package=zonebuilder)
 [![CRAN RStudio mirror
 downloads](https://cranlogs.r-pkg.org/badges/grand-total/zonebuilder)](https://www.r-pkg.org/pkg/zonebuilder)
-[DOI](https://doi.org/10.31219/osf.io/vncgw)
+[DOI](https://doi.org/10.5311/JOSIS.2022.24.172)
 <!-- badges: end -->
 
 The goal of zonebuilder is to break up large geographic regions such as cities into manageable zones.
-Zoning systems are important in many fields, including demographics, economy, health, and transport. The zones have standard configuration, which enabled comparability across cities. See its website at [zonebuilders.github.io/zonebuilder](https://zonebuilders.github.io/zonebuilder/).
+Zoning systems are important in many fields, including demographics, economy, health, and transport. The zones have standard configuration, which enabled comparability across cities. See its website at [zonebuilders.github.io/zonebuilder](https://zonebuilders.github.io/zonebuilder/) and the academic paper that describes the package in detail [here (Lovelace et al. 2022)](https://doi.org/10.5311/JOSIS.2022.24.172).
 
 ## Installation
 
@@ -53,7 +53,11 @@ Attaching the package provides the example datasets `london_a()` and `london_c()
 ```{r}
 library(zonebuilder)
 library(tmap)
-tm_shape(london_a()) + tm_borders() + tm_shape(london_c()) + tm_dots("red")
+tmap_mode("plot")
+tm_shape(london_a()) +
+  tm_borders() +
+  tm_shape(london_c()) +
+  tm_dots("red")
 ```
 
 The main function `zb_zone` breaks this geographical scale into zones. The default settings follow the **ClockBoard** configuration:
@@ -99,11 +103,25 @@ It may be worth checking-in in a [discussion post](https://github.com/zonebuilde
 
 ## Citation
 
-Watch this space.
-
-
-<!-- tmap_arrange( -->
-<!--   zb_view(zb_doughnut(london_c(), london_a(), n_circles = 5), title = "Doughnuts"), -->
-<!--   zb_view(zb_segment(london_c(), n_segments = 20), title = "Segments") -->
-<!--  ) -->
+Please cite the package as follows (Lovelace et al. 2022):
 
+```
+@article{lovelace_clockboard_2022,
+  title = {{{ClockBoard}}: {{A}} Zoning System for Urban Analysis},
+  shorttitle = {{{ClockBoard}}},
+  author = {Lovelace, Robin and Tennekes, Martijn and Carlino, Dustin},
+  date = {2022-06-20},
+  journaltitle = {Journal of Spatial Information Science},
+  number = {24},
+  pages = {63--85},
+  issn = {1948-660X},
+  doi = {10.5311/JOSIS.2022.24.172},
+  url = {https://josis.org/index.php/josis/article/view/172},
+  urldate = {2022-07-02},
+  abstract = {Zones are the building blocks of urban analysis. Fields ranging from demographics to transport planning routinely use zones - spatially contiguous areal units that break-up continuous space into discrete chunks - as the foundation for diverse analysis techniques. Key methods such as origin-destination analysis and choropleth mapping rely on zones with appropriate sizes, shapes and coverage. However, existing zoning systems are sub-optimal in many urban analysis contexts, for three main reasons: 1) administrative zoning systems are often based on somewhat arbitrary factors; 2) zoning systems that are evidence-based (e.g., based on equal population size) are often highly variable in size and shape, reducing their utility for inter-city comparison; and 3) official zoning systems in many places simply do not exist or are unavailable. We set out to develop a flexible, open and scalable solution to these problems. The result is the zonebuilder project (with R, Rust and Python implementations), which was used to create the ClockBoard zoning system. ClockBoard consists of 12 segments emanating from a central place and divided by concentric rings with radii that increase in line with the triangular number sequence (1, 3, 6 km etc). 'ClockBoards' thus create a consistent visual frame of reference for monocentric cities that is reminiscent of clocks and a dartboard. This paper outlines the design and potential uses of the ClockBoard zoning system in the historical context, and discusses future avenues for research into the design and assessment of zoning systems.},
+  issue = {24},
+  langid = {english},
+  keywords = {modifiable area unit problem},
+  file = {C:\Users\georl_admin\Zotero\storage\QRQDMJSH\Lovelace et al. - 2022 - ClockBoard A zoning system for urban analysis.pdf}
+}
+```
\ No newline at end of file
diff --git a/README.md b/README.md
index 4963a0a..0adf55b 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,7 @@
 # zonebuilder
 
 <!-- badges: start -->
+
 <!-- [![Codecov test coverage](https://codecov.io/gh/zonebuilders/zonebuilder/branch/master/graph/badge.svg)](https://codecov.io/gh/zonebuilders/zonebuilder?branch=master) -->
 
 [![R-CMD-check](https://github.com/zonebuilders/zonebuilder/workflows/R-CMD-check/badge.svg)](https://github.com/zonebuilders/zonebuilder/actions)
@@ -11,14 +12,16 @@
 status](https://www.r-pkg.org/badges/version/zonebuilder)](https://CRAN.R-project.org/package=zonebuilder)
 [![CRAN RStudio mirror
 downloads](https://cranlogs.r-pkg.org/badges/grand-total/zonebuilder)](https://www.r-pkg.org/pkg/zonebuilder)
-[DOI](https://doi.org/10.31219/osf.io/vncgw) <!-- badges: end -->
+[DOI](https://doi.org/10.5311/JOSIS.2022.24.172) <!-- badges: end -->
 
 The goal of zonebuilder is to break up large geographic regions such as
 cities into manageable zones. Zoning systems are important in many
 fields, including demographics, economy, health, and transport. The
 zones have standard configuration, which enabled comparability across
 cities. See its website at
-[zonebuilders.github.io/zonebuilder](https://zonebuilders.github.io/zonebuilder/).
+[zonebuilders.github.io/zonebuilder](https://zonebuilders.github.io/zonebuilder/)
+and the academic paper that describes the package in detail [here
+(Lovelace et al. 2022)](https://doi.org/10.5311/JOSIS.2022.24.172).
 
 ## Installation
 
@@ -47,7 +50,11 @@ geographic boundary and the centre of London:
 ``` r
 library(zonebuilder)
 library(tmap)
-tm_shape(london_a()) + tm_borders() + tm_shape(london_c()) + tm_dots("red")
+tmap_mode("plot")
+tm_shape(london_a()) +
+  tm_borders() +
+  tm_shape(london_c()) +
+  tm_dots("red")
 ```
 
 <img src="man/figures/README-unnamed-chunk-3-1.png" width="100%" />
@@ -64,22 +71,21 @@ zb_plot(london_zones)
 
 The idea behind this zoning system is based on the following principles:
 
--   Most cities have a centre, the ‘heart’ of the city. Therefore, the
-    zones are distributed around the centre.
--   Typically, the population is much denser in and around the centre
-    and also the traffic intensity is higher. Therefore, the zones are
-    smaller in and around the centre.
--   The rings (so A, B, C, D, etc) reflect the proximity to the centre
-    point. The distances from the outer borders of the rings A, B, C, D,
-    etc. follow the triangular number sequence 1, 3, 6, 10, etc. This
-    means that in everyday life use, within zone A everything is in
-    walking distance, from ring B to the centre requires a bike, from
-    zone C and further to the centre typically requires public
-    transport.
--   Regarding direction relative to the centre, we use the clock
-    analogy, since most people are familiar with that. So each ring
-    (annuli) is divided into 12 segments, where segment 12 is directed
-    at 12:00, segment 1 at 1:00 etc.
+- Most cities have a centre, the ‘heart’ of the city. Therefore, the
+  zones are distributed around the centre.
+- Typically, the population is much denser in and around the centre and
+  also the traffic intensity is higher. Therefore, the zones are smaller
+  in and around the centre.
+- The rings (so A, B, C, D, etc) reflect the proximity to the centre
+  point. The distances from the outer borders of the rings A, B, C, D,
+  etc. follow the triangular number sequence 1, 3, 6, 10, etc. This
+  means that in everyday life use, within zone A everything is in
+  walking distance, from ring B to the centre requires a bike, from zone
+  C and further to the centre typically requires public transport.
+- Regarding direction relative to the centre, we use the clock analogy,
+  since most people are familiar with that. So each ring (annuli) is
+  divided into 12 segments, where segment 12 is directed at 12:00,
+  segment 1 at 1:00 etc.
 
 The package `zonebuilder` does not only create zoning systems based on
 the CloadBoard layout as illustrated below.
@@ -126,10 +132,23 @@ opening an issue.
 
 ## Citation
 
-Watch this space.
-
-<!-- tmap_arrange( -->
-<!--   zb_view(zb_doughnut(london_c(), london_a(), n_circles = 5), title = "Doughnuts"), -->
-<!--   zb_view(zb_segment(london_c(), n_segments = 20), title = "Segments") -->
-<!--  ) -->
- 
\ No newline at end of file
+Please cite the package as follows (Lovelace et al. 2022):
+
+    @article{lovelace_clockboard_2022,
+      title = {{{ClockBoard}}: {{A}} Zoning System for Urban Analysis},
+      shorttitle = {{{ClockBoard}}},
+      author = {Lovelace, Robin and Tennekes, Martijn and Carlino, Dustin},
+      date = {2022-06-20},
+      journaltitle = {Journal of Spatial Information Science},
+      number = {24},
+      pages = {63--85},
+      issn = {1948-660X},
+      doi = {10.5311/JOSIS.2022.24.172},
+      url = {https://josis.org/index.php/josis/article/view/172},
+      urldate = {2022-07-02},
+      abstract = {Zones are the building blocks of urban analysis. Fields ranging from demographics to transport planning routinely use zones - spatially contiguous areal units that break-up continuous space into discrete chunks - as the foundation for diverse analysis techniques. Key methods such as origin-destination analysis and choropleth mapping rely on zones with appropriate sizes, shapes and coverage. However, existing zoning systems are sub-optimal in many urban analysis contexts, for three main reasons: 1) administrative zoning systems are often based on somewhat arbitrary factors; 2) zoning systems that are evidence-based (e.g., based on equal population size) are often highly variable in size and shape, reducing their utility for inter-city comparison; and 3) official zoning systems in many places simply do not exist or are unavailable. We set out to develop a flexible, open and scalable solution to these problems. The result is the zonebuilder project (with R, Rust and Python implementations), which was used to create the ClockBoard zoning system. ClockBoard consists of 12 segments emanating from a central place and divided by concentric rings with radii that increase in line with the triangular number sequence (1, 3, 6 km etc). 'ClockBoards' thus create a consistent visual frame of reference for monocentric cities that is reminiscent of clocks and a dartboard. This paper outlines the design and potential uses of the ClockBoard zoning system in the historical context, and discusses future avenues for research into the design and assessment of zoning systems.},
+      issue = {24},
+      langid = {english},
+      keywords = {modifiable area unit problem},
+      file = {C:\Users\georl_admin\Zotero\storage\QRQDMJSH\Lovelace et al. - 2022 - ClockBoard A zoning system for urban analysis.pdf}
+    }
diff --git a/cran-comments.md b/cran-comments.md
index 7c69e76..5f2ecd3 100644
--- a/cran-comments.md
+++ b/cran-comments.md
@@ -1,4 +1,6 @@
-Resubmitting after fixes to enable the package to work with sf 1.0-1 and beyond.
+Many updates enabling tests to pass on CRAN, after the package was removed due to failing tests.
+
+I have fixed broken URLs since last submission.
 
 ## Test environments
 * local R installation, R 4.1.0
diff --git a/data-raw/fix-polygons.R b/data-raw/fix-polygons.R
index c14fb96..5bec4a0 100644
--- a/data-raw/fix-polygons.R
+++ b/data-raw/fix-polygons.R
@@ -17,9 +17,6 @@ qtm(sf::st_make_valid(z))
 tmap_options(check.and.fix = TRUE)
 qtm(z)
 
-zb_view(z)
-
-
 lnd_a = zonebuilder::london_a()
 sf::st_is_valid(lnd_a)
 sf::st_is_valid(london_c())
diff --git a/man/figures/README-unnamed-chunk-3-1.png b/man/figures/README-unnamed-chunk-3-1.png
index b716f35..dd10e6a 100644
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index 282da64..eb2fa71 100644
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index aa1e8f9..e9b3e5f 100644
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index 3760a27..afe5554 100644
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index 3750cfe..a196686 100644
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diff --git a/man/figures/README-unnamed-chunk-6-1.png b/man/figures/README-unnamed-chunk-6-1.png
index 495a424..acf1a14 100644
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diff --git a/man/geo_select_aeq.Rd b/man/geo_select_aeq.Rd
new file mode 100644
index 0000000..e174e47
--- /dev/null
+++ b/man/geo_select_aeq.Rd
@@ -0,0 +1,26 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/from_stplanr.R
+\name{geo_select_aeq}
+\alias{geo_select_aeq}
+\alias{geo_select_aeq.sf}
+\alias{geo_select_aeq.sfc}
+\title{Azimuthal Equidistant Projection}
+\usage{
+\method{geo_select_aeq}{sf}(shp)
+
+\method{geo_select_aeq}{sfc}(shp)
+
+geo_select_aeq(shp)
+}
+\arguments{
+\item{shp}{An sf object.}
+}
+\value{
+A CRS string for an Azimuthal Equidistant projection.
+}
+\description{
+Returns a CRS string for an Azimuthal Equidistant projection centered on the midpoint of an sf object's coordinates.
+}
+\details{
+Azimuthal Equidistant Projection
+}
diff --git a/man/zb_view.Rd b/man/zb_view.Rd
deleted file mode 100644
index dd88779..0000000
--- a/man/zb_view.Rd
+++ /dev/null
@@ -1,29 +0,0 @@
-% Generated by roxygen2: do not edit by hand
-% Please edit documentation in R/plot.R
-\name{zb_view}
-\alias{zb_view}
-\title{View zones}
-\usage{
-zb_view(z, alpha = 0.4, palette = c("rings", "hcl", "dartboard"), title = NULL)
-}
-\arguments{
-\item{z}{An `sf` object containing zones covering the region}
-
-\item{alpha}{Alpha transparency, number between 0 (fully transparent) and 1 (not transparent)}
-
-\item{palette}{Palette type, one of \code{"hcl"} (a palette based on the HCL color space), \code{"rings"} (a palette which colors the rings using the YlOrBr color brewer palette), \code{"dartboard"} (a palette which resembles a dartboard)}
-
-\item{title}{The title of the plot}
-}
-\value{
-An interactive map created with `tmap`
-}
-\description{
-This function opens an interactive map of the zones
-}
-\examples{
-\donttest{
-z = zb_zone(london_c(), london_a())
-zb_view(z, palette = "rings")
-}
-}
diff --git a/man/zb_zone.Rd b/man/zb_zone.Rd
index f57382d..b0a22d6 100644
--- a/man/zb_zone.Rd
+++ b/man/zb_zone.Rd
@@ -57,18 +57,7 @@ with 12 representing North, 3 representing East, 6 Sounth and 9 Western segments
 \examples{
 # default settings
 z = zb_zone(london_c(), london_a())
-\donttest{
-zb_plot(z)
-if (require(tmap)) {
-  zb_view(z)
-  
-  z = zb_zone("Berlin")
-  zb_view(z)
-}
-
-# variations
 zb_plot(zb_zone(london_c(), london_a(), n_circles = 2))
 zb_plot(zb_zone(london_c(), london_a(), n_circles = 4, distance = 2, distance_growth = 0))
 zb_plot(zb_zone(london_c(), london_a(), n_circles = 3, n_segments = c(1,4,8)))
 }
-}
diff --git a/vignettes/paper.Rmd b/vignettes/paper.Rmd
index cdfb00d..2d63c0e 100644
--- a/vignettes/paper.Rmd
+++ b/vignettes/paper.Rmd
@@ -112,7 +112,7 @@ Gerrymandering has since been the topic of countless academic papers that is the
 
 Research has made great progress in mathematical analysis of zones and more objective assessment of the impacts that the nature of zoning systems can have on zone-based statistics (such as number of votes for a particular party in each zone) and outcomes.
 The gerrymandering problem (in itself is a manifestation of the modifiable area unit problem) can be described as a mathematical optimization problem: "$n$ units are grouped into $k$ zones such that some cost function is optimized, subject to constraints on the topology of the zones" [@chou_taming_2006].
-Prior work has demonstrated the sensitivity of urban analysis outcomes to zone system design, from the way cities are visualized to the [impact of the nature of 'traffic analysis zones' on transport model outputs](http://www.iasi.cnr.it/ewgt/13conference/145_binetti.pdf). 
+Prior work has demonstrated the sensitivity of urban analysis outcomes to zone system design, from the way cities are visualized to the impact of the nature of 'traffic analysis zones' on transport model outputs. 
 In fact, this problem is a concise definition of the broader "zoning problem" that starts from the assumption that zones are to be composed of one or more basic statistical units (BSUs) [@jelinski_modifiable_1996; @chandra_multi-objective_2021] .
 Although the range of outcomes is a finite combinatorial optimisation problem (which combination of BSU-zone aggregations satisfy/optimize some pre-determined criteria) the zoning problem is still hard: "there are a tremendously large number of alternative partitions, a similar number of different results, and only a slightly smaller number of different interpretations" [@openshaw_optimal_1977].
 
@@ -587,7 +587,7 @@ We explored the possibility of 'joining' ClockBoard systems that met, with the '
 An alternative and approach to developing zoning systems for complex and polycentric settlements not implemented in this paper is to build them on exisiting Discrete Global Grid Systems (DGGS) such as the S2 and H3 global zoning systems developed by Google and Uber respectively [@bondaruk_assessing_2020], and the [QTM Generator](https://github.com/paulojraposo/QTM) developed by Paulo Raposo [@raposo_virtual_2019].
 This would have advantages for flexibility, with DGGSs able to generate grids with zone sizes that are more evidence-based, for example by respondingM to geographic data such as population density.
 DGGS based zoning systems would also enable greater determinism, with each of S2's ~7 quintillion ($6 * 4^{30}$ or $\approx6.9*10^{18}$) and H3's ~700 trillion ($\approx5.7 * 10^{14}$) base zones having a unique reference code that is machine readable (ClockBoards are arguably deterministic with 'zone B12, Leeds, UK' referring to an unambiguous area, although ClockBoards depend on an unambiguous definition of 'city centre' which may not be available or requires a single unique source of city centre points).
-Theses beneficial features would be gained at the expense of simplicity: DGGSs are complex and have hard-to-remember cell IDs such as [e66ef376f790adf8a5af7fca9e6e422c03c9143f](https://developers.google.com/maps/documentation/gaming/concepts_playable_locations) (S2) and [8a283082a677fff](https://h3geo.org/docs/quickstart) (H3); they also have high computational requirements [@bondaruk_assessing_2020], compared with the comparatively simple ClockBoard system.
+Theses beneficial features would be gained at the expense of simplicity: DGGSs are complex and have hard-to-remember cell IDs such as [e66ef376f790adf8a5af7fca9e6e422c03c9143f](https://developers.google.com/maps/documentation/gaming/concepts_playable_locations) (S2) and [8a283082a677fff](https://h3geo.org/docs/quickstart/) (H3); they also have high computational requirements [@bondaruk_assessing_2020], compared with the comparatively simple ClockBoard system.
 
 While the utility of the zoning system is likely to be limited in many settings by the limitations outlined above, we believe that there are settings in which ClockBoard could provide substantial benefits, as demonstrated in three example applications.
 These demonstrated potential use cases for informal communication about and navigation within cities; exploratory data analysis and visualisation of geographic data within a single city; and visual and quantitative comparison of geographic phenomena between cities.
diff --git a/vignettes/references.bib b/vignettes/references.bib
index e90de46..1f5208c 100644
--- a/vignettes/references.bib
+++ b/vignettes/references.bib
@@ -3,8 +3,6 @@ @Article{bondaruk_assessing_2020
   volume = {74},
   issn = {1195-1036},
   shorttitle = {Assessing the state of the art in {Discrete} {Global} {Grid} {Systems}},
-  url = {https://cdnsciencepub.com/doi/abs/10.1139/geomat-2019-0015},
-  doi = {10.1139/geomat-2019-0015},
   number = {1},
   urldate = {2021-08-12},
   journal = {Geomatica},
@@ -19,8 +17,6 @@ @Article{raposo_virtual_2019
   title = {A {Virtual} {Globe} {Using} a {Discrete} {Global} {Grid} {System} to {Illustrate} the {Modifiable} {Areal} {Unit} {Problem}},
   volume = {54},
   issn = {0317-7173},
-  url = {https://www.utpjournals.press/doi/full/10.3138/cart.54.1.2018-0015},
-  doi = {10/gmf8dg},
   abstract = {In the same way that discrete global grid systems (DGGS) are used to index data on the spherical Earth, they can aggregate point data, with their spherical polygons serving as bins. DGGS are particularly useful at multiple map scales because they are spatially hierarchical and exist on the sphere or ellipsoid, allowing large or small scale binning without projection distortion. We use DGGS in a free and open-source pedagogical tool for teaching students about the modifiable areal unit problem (MAUP). Our software application uses Dutton’s quaternary triangular mesh (QTM) to bin global data points geodesically with counts or measures of any theme at multiple levels. Users can interactively select the level to which the data are binned by the QTM, as well as translate the whole tessellation east or west so that points fall into and out of different bins. These two functions illustrate the scaling and zoning aspects of the MAUP with dynamically-drawn choropleths on the surface of a virtual globe that the user can zoom and rotate, allowing visualization at virtually any cartographic scale. Users may also select various quantile classifications to further explore issues in visualizing aggregate data. In addition to presenting this new tool, we highlight the importance, especially at smaller scales, of using geodesic point-in-polygon intersection detection, rather than the projected 2D methods typically used by geographic information systems.},
   number = {1},
   urldate = {2021-07-30},
@@ -37,8 +33,6 @@ @Article{hernandez-perez_grid_2011
   title = {Grid {Generation} {Issues} in the {CFD} {Modelling} of {Two}-{Phase} {Flow} in a {Pipe}},
   volume = {3},
   issn = {1757-482X},
-  url = {https://doi.org/10.1260/1757-482X.3.1.13},
-  doi = {10/bgcrzt},
   abstract = {The grid generation issues found in the 3D simulation of two-phase flow in a pipe using Computational Fluid Dynamics (CFD) are discussed in this paper. Special attention is given to the effect of the element type and structure of the mesh. The simulations were carried out using the commercial software package STAR-CCM+, which is designed for numerical simulation of continuum mechanics problems. The model consisted of a cylindrical vertical pipe. Different mesh structures were employed in the computational domain. The condition of two-phase flow was simulated with the Volume of Fluid (VOF) model, taking into consideration turbulence effects using the k-e model. The results showed that there is a strong dependency of the flow behaviour on the mesh employed. The best result was obtained with the grid known as butterfly grid, while the cylindrical mesh produced misleading results. The simulation was validated against experimental results.},
   language = {en},
   number = {1},
@@ -57,8 +51,6 @@ @Article{alidadi_beyond_2018
   volume = {22},
   issn = {1226-5934},
   shorttitle = {Beyond monocentricity},
-  url = {https://doi.org/10.1080/12265934.2017.1329024},
-  doi = {10/gmf8db},
   abstract = {This research examines the spatial distribution of employment in Tehran metropolitan region as one of the most populated regions in West Asia. For this aim, our approach includes three steps; first, the paper investigates the level of monocentricity or the primacy of the main core, then, the paper utilises various methodologies to identify the employment subcenters in the region; and finally, the importance of identified centres is estimated by polycentric employment function. To do this, data obtained from Statistical Centre of Iran for 2006 and 2011 is provided in sub-district level, the smallest geographical unit. Results revealed that monocentric model is not able to explain the spatial distribution of employment in TMR; also, the main core loses its importance with the passage of time. Applying different methodologies for TMR identified 3 subcenters in 2006; whereas, it reached to 7 subcenters in 2011. In the last step, the deployed polycentric employment function explained 42\% and 51\% of total employment distribution throughout TMR in 2006 and 2011 respectively.},
   number = {1},
   urldate = {2021-08-07},
@@ -66,9 +58,6 @@ @Article{alidadi_beyond_2018
   author = {Mehdi Alidadi and Hashem Dadashpoor},
   month = {jan},
   year = {2018},
-  note = {Publisher: Routledge
-\_eprint: https://doi.org/10.1080/12265934.2017.1329024},
-  keywords = {Monocentricity, Tehran metropolitan region, polycentricity, spatial structure, sub-centring},
   pages = {38--58},
 }
 
@@ -76,8 +65,6 @@ @Article{vinoth_kumar_spatio-temporal_2007
   title = {Spatio-temporal analysis for monitoring urban growth – a case study of {Indore} {City}},
   volume = {35},
   issn = {0974-3006},
-  url = {https://doi.org/10.1007/BF02991829},
-  doi = {10/cn746z},
   abstract = {Urban sprawl is characterized by haphazard patchwork of development, which leads to an improper development in any city. To prevent this kind of sprawl in future, it is necessary to monitor the growth of the city. Hence, an attempt has been made in the present study to monitor the urban growth over a period of time by employing Remote Sensing and Geographic Information System techniques in conjunction with Shannon entropy. Shannon entropy is a measure to determine the compactness or dispersion of built-up land growth in the urban areas. The growth patterns of urban built-up land have been studied initially by dividing the area into four zones. The observations have been made with respect to each zone. Then, the study area has been divided into concentric circles of 1 km buffers and the growth patterns have been studied based on urban built-up density with respect to each circular buffer in all four zones. These observations have been integrated with road network to check the influence of infrastructure on haphazard urban growth. It has been found from the study that Shannon entropy is a good measure to determine the spatial concentration or dispersion of built-up land in the city. The study also proved the potential of RS and GIS techniques in the spatio-temporal analysis of urban growth trends and their consequences in the lands adjoining to urban areas.},
   language = {en},
   number = {1},
@@ -91,7 +78,6 @@ @Article{vinoth_kumar_spatio-temporal_2007
 
 @TechReport{hart_use_1991,
   title = {The use of visual cues for vehicle control and navigation},
-  url = {https://ntrs.nasa.gov/citations/19920012225},
   abstract = {At least three levels of control are required to operate most vehicles: (1) inner-loop control to counteract the momentary effects of disturbances on vehicle position; (2) intermittent maneuvers to avoid obstacles, and (3) outer-loop control to maintain a planned route. Operators monitor dynamic optical relationships in their immediate surroundings to estimate momentary changes in forward, lateral, and vertical position, rates of change in speed and direction of motion, and distance from obstacles. The process of searching the external scene to find landmarks (for navigation) is intermittent and deliberate, while monitoring and responding to subtle changes in the visual scene (for vehicle control) is relatively continuous and 'automatic'. However, since operators may perform both tasks simultaneously, the dynamic optical cues available for a vehicle control task may be determined by the operator's direction of gaze for wayfinding. An attempt to relate the visual processes involved in vehicle control and wayfinding is presented. The frames of reference and information used by different operators (e.g., automobile drivers, airline pilots, and helicopter pilots) are reviewed with particular emphasis on the special problems encountered by helicopter pilots flying nap of the earth (NOE). The goal of this overview is to describe the context within which different vehicle control tasks are performed and to suggest ways in which the use of visual cues for geographical orientation might influence visually guided control activities.},
   number = {N92-21468},
   urldate = {2021-07-26},
@@ -99,9 +85,6 @@ @TechReport{hart_use_1991
   author = {Sandra G. Hart and Vernol Battiste},
   month = {apr},
   year = {1991},
-  note = {NTRS Author Affiliations: NASA Ames Research Center
-NTRS Document ID: 19920012225
-NTRS Research Center: Legacy CDMS (CDMS)},
   keywords = {BEHAVIORAL SCIENCES},
 }
 
@@ -109,8 +92,6 @@ @Article{jelinski_modifiable_1996
   title = {The modifiable areal unit problem and implications for landscape ecology},
   volume = {11},
   issn = {1572-9761},
-  url = {https://doi.org/10.1007/BF02447512},
-  doi = {10/c6gjwq},
   abstract = {Landscape ecologists often deal with aggregated data and multiscaled spatial phenomena. Recognizing the sensitivity of the results of spatial analyses to the definition of units for which data are collected is critical to characterizing landscapes with minimal bias and avoidance of spurious relationships. We introduce and examine the effect of data aggregation on analysis of landscape structure as exemplified through what has become known, in the statistical and geographical literature, as theModifiable Areal Unit Problem (MAUP). The MAUP applies to two separate, but interrelated, problems with spatial data analysis. The first is the “scale problem”, where the same set of areal data is aggregated into several sets of larger areal units, with each combination leading to different data values and inferences. The second aspect of the MAUP is the “zoning problem”, where a given set of areal units is recombined into zones that are of the same size but located differently, again resulting in variation in data values and, consequently, different conclusions. We conduct a series of spatial autocorrelation analyses based on NDVI (Normalized Difference Vegetation Index) to demonstrate how the MAUP may affect the results of landscape analysis. We conclude with a discussion of the broader-scale implications for the MAUP in landscape ecology and suggest approaches for dealing with this issue.},
   language = {en},
   number = {3},
@@ -126,8 +107,6 @@ @Article{chandra_multi-objective_2021
   title = {A multi-objective genetic algorithm approach to design optimal zoning systems for freight transportation planning},
   volume = {92},
   issn = {09666923},
-  url = {https://linkinghub.elsevier.com/retrieve/pii/S0966692321000909},
-  doi = {10/gk7stb},
   language = {en},
   urldate = {2021-07-15},
   journal = {Journal of Transport Geography},
@@ -152,7 +131,6 @@ @Article{bryant_worcestershire_2007
   title = {The {Worcestershire} {Tithe} and {Enclosure} {Map} {Project}: creating a research resource},
   volume = {29},
   shorttitle = {The {Worcestershire} {Tithe} and {Enclosure} {Map} {Project}},
-  doi = {10/gkb5qs},
   number = {1},
   journal = {Landscape History},
   author = {Victoria Bryant and Maggi Noke},
@@ -164,8 +142,6 @@ @Article{openshaw_optimal_1977
   title = {Optimal zoning systems for spatial interaction models},
   volume = {9},
   issn = {0308-518X},
-  url = {http://www.envplan.com/abstract.cgi?id=a090169},
-  doi = {10/btqf8f},
   number = {2},
   journal = {Environment and Planning A},
   author = {S Openshaw},
@@ -176,7 +152,6 @@ @Article{openshaw_optimal_1977
 @Article{dorling_area_2011,
   title = {Area {Cartograms}: {Their} {Use} and {Creation}},
   issn = {0 306-6142},
-  doi = {10/bmhcfj},
   abstract = {This book provides an introduction to the concept of cartograms, the various methods of creating them, and some common applications. It contains a large number of colour figures to visually demonstrate the power of cartograms, drawn from many different sources.},
   journal = {The Map Reader: Theories of Mapping Practice and Cartographic Representation},
   author = {Daniel Dorling},
@@ -191,8 +166,6 @@ @Article{lovelace_propensity_2017
   copyright = {Copyright (c) 2016 Robin Lovelace, Anna Goodman, Rachel Aldred, Nikolai Berkoff, Ali Abbas, James Woodcock},
   issn = {1938-7849},
   shorttitle = {The {Propensity} to {Cycle} {Tool}},
-  url = {https://www.jtlu.org/index.php/jtlu/article/view/862},
-  doi = {10/gfgzf7},
   abstract = {Getting people cycling is an increasingly common objective in transport planning institutions worldwide. A growing evidence base indicates that high quality infrastructure can boost local cycling rates. Yet for infrastructure and other cycling measures to be effective, it is important to intervene in the right places, such as along ‘desire lines’ of high latent demand. This creates the need for tools and methods to help answer the question ‘where to build?’. Following a brief review of the policy and research context related to this question, this paper describes the design, features and potential applications of such a tool. The Propensity to Cycle Tool (PCT) is an online, interactive planning support system that was initially developed to explore and map cycling potential across England (see www.pct.bike). Based on origin-destination data it models cycling levels at area, desire line, route and route network levels, for current levels of cycling, and for scenario-based ‘cycling futures.’ Four scenarios are presented, including ‘Go Dutch’ and ‘Ebikes,’ which explore what would happen if English people had the same propensity to cycle as Dutch people and the potential impact of electric cycles on cycling uptake. The cost effectiveness of investment depends not only on the number of additional trips cycled, but on wider impacts such as health and carbon benefits. The PCT reports these at area, desire line, and route level for each scenario. The PCT is open source, facilitating the creation of scenarios and deployment in new contexts. We conclude that the PCT illustrates the potential of online tools to inform transport decisions and raises the wider issue of how models should be used in transport planning.},
   language = {en},
   number = {1},
@@ -208,8 +181,6 @@ @Article{wills_persistence_2016
   title = {Persistence of {Neighborhood} {Demographic} {Influences} over {Long} {Phylogenetic} {Distances} {May} {Help} {Drive} {Post}-{Speciation} {Adaptation} in {Tropical} {Forests}},
   volume = {11},
   issn = {1932-6203},
-  url = {https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0156913},
-  doi = {10/f9htqm},
   abstract = {Studies of forest dynamics plots (FDPs) have revealed a variety of negative density-dependent (NDD) demographic interactions, especially among conspecific trees. These interactions can affect growth rate, recruitment and mortality, and they play a central role in the maintenance of species diversity in these complex ecosystems. Here we use an equal area annulus (EAA) point-pattern method to comprehensively analyze data from two tropical FDPs, Barro Colorado Island in Panama and Sinharaja in Sri Lanka. We show that these NDD interactions also influence the continued evolutionary diversification of even distantly related tree species in these FDPs. We examine the details of a wide range of these interactions between individual trees and the trees that surround them. All these interactions, and their cumulative effects, are strongest among conspecific focal and surrounding tree species in both FDPs. They diminish in magnitude with increasing phylogenetic distance between heterospecific focal and surrounding trees, but do not disappear or change the pattern of their dependence on size, density, frequency or physical distance even among the most distantly related trees. The phylogenetic persistence of all these effects provides evidence that interactions between tree species that share an ecosystem may continue to promote adaptive divergence even after the species’ gene pools have become separated. Adaptive divergence among taxa would operate in stark contrast to an alternative possibility that has previously been suggested, that distantly related species with dispersal-limited distributions and confronted with unpredictable neighbors will tend to converge on common strategies of resource use. In addition, we have also uncovered a positive density-dependent effect: growth rates of large trees are boosted in the presence of a smaller basal area of surrounding trees. We also show that many of the NDD interactions switch sign rapidly as focal trees grow in size, and that their cumulative effect can strongly influence the distributions and species composition of the trees that surround the focal trees during the focal trees’ lifetimes.},
   language = {en},
   number = {6},
@@ -227,8 +198,6 @@ @Article{paez_exploring_2006
   title = {Exploring contextual variations in land use and transport analysis using a probit model with geographical weights},
   volume = {14},
   issn = {0966-6923},
-  url = {https://www.sciencedirect.com/science/article/pii/S0966692305000906},
-  doi = {10/b28gvg},
   abstract = {A majority of statistical methods used in the analysis of land use and transportation systems implicitly carry the assumption that relationships are constant across locations or individuals, thus ignoring contextual variation due to geographical or socio-economic heterogeneity. In some cases, where the assumption of constant relationships is questionable, market segmentation procedures are used to study varying relationships. More recently, methodological developments, and a greater awareness of the importance of geography, have led to increasingly sophisticated ways to explore varying relationships in land use and transportation modeling. The objective of this paper is to propose a simple probit model to explore contextual variability in continuous-space. Some conceptual and technical issues are discussed, and an example is presented that reanalyzes land use change using data from California’s BART system. The results of the example suggest that considerable parametric variation exists across geographical space, and thus underlines the relevance of contextual effects.},
   language = {en},
   number = {3},
@@ -246,8 +215,6 @@ @Article{teulade-denantes_routes_2015
   volume = {2015},
   issn = {1948-660X},
   shorttitle = {Routes visualization},
-  url = {http://www.josis.org/index.php/josis/article/view/230},
-  doi = {10/gjhh7h},
   abstract = {Routes visualization: Automated placement of multiple route symbols along a physical network infrastructure},
   number = {11},
   urldate = {2021-03-08},
@@ -263,8 +230,6 @@ @Article{anderson_augmented_2018
   volume = {16},
   issn = {1478-0771},
   shorttitle = {Augmented space planning},
-  url = {https://doi.org/10.1177/1478077118778586},
-  doi = {10/gghqbf},
   abstract = {We developed a suite of procedural algorithms for space planning in commercial offices. These algorithms were benchmarked against 13,000 actual offices designed by human architects. The algorithm performed as well as an architect on 77\% of offices, and achieved a higher capacity in an additional 6\%, all while following a set of space standards. If the algorithm used the space standards the same way as an architect (a more relaxed interpretation), the algorithm achieved a 97\% match rate, which means that the algorithm completed this design task as well as a designer and in a shorter time. The benchmarking of a layout algorithm against thousands of existing designs is a novel contribution of this article, and we argue that it might be a first step toward a more comprehensive method to automate parts of the office layout process.},
   language = {en},
   number = {2},
@@ -282,8 +247,6 @@ @Article{onrust_ecologically_2017
   title = {Ecologically {Sound} {Procedural} {Generation} of {Natural} {Environments}},
   volume = {2017},
   issn = {1687-7047},
-  url = {https://www.hindawi.com/journals/ijcgt/2017/7057141/},
-  doi = {10/gjhh7g},
   abstract = {Current techniques for the creation and exploration of virtual worlds are largely unable to generate sound natural environments from ecological data and to provide interactive web-based visualizations of such detailed environments. We tackle this challenge and propose a novel framework that (i) explores the advantages of landscape maps and ecological statistical data, translating them to an ecologically sound plant distribution, and (ii) creates a visually convincing 3D representation of the natural environment suitable for its interactive visualization over the web. Our vegetation model improves techniques from procedural ecosystem generation and neutral landscape modeling. It is able to generate diverse ecological sound plant distributions directly from landscape maps with statistical ecological data. Our visualization model integrates existing level of detail and illumination techniques to achieve interactive frame rates and improve realism. We validated with ecology experts the outcome of our framework using two case studies and concluded that it provides convincing interactive visualizations of large natural environments.},
   language = {en},
   urldate = {2021-03-08},
@@ -299,8 +262,6 @@ @Article{mustafa_procedural_2020
   title = {Procedural generation of flood-sensitive urban layouts},
   volume = {47},
   issn = {2399-8083},
-  url = {https://doi.org/10.1177/2399808318812458},
-  doi = {10/gjhh7f},
   abstract = {Aside from modeling geometric shape, three-dimensional (3D) urban procedural modeling has shown its value in understanding, predicting and/or controlling effects of shape on design and urban planning. In this paper, instead of the construction of flood resistant measures, we create a procedural generation system for designing urban layouts that passively reduce water depth during a flooding scenario. Our tool enables exploring designs that passively lower flood depth everywhere or mostly in chosen key areas. Our approach tightly integrates a hydraulic model and a parameterized urban generation system with an optimization engine so as to find the least cost modification to an initial urban layout design. Further, due to the computational cost of a fluid simulation, we train neural networks to assist with accelerating the design process. We have applied our system to several real-world locations and have obtained improved 3D urban models in just a few seconds.},
   language = {en},
   number = {5},
@@ -318,8 +279,6 @@ @Article{lin_cartographic_2017
   title = {A cartographic modeling approach to isopleth mapping},
   volume = {31},
   issn = {1365-8816},
-  url = {https://doi.org/10.1080/13658816.2016.1207776},
-  doi = {10/gjhh7d},
   abstract = {Isopleth maps depict different types of standardized data densities, general ratios/rates, and proportions/percentages. In this study, we describe different paths each type of standardized data takes to construct isoplethic surfaces in a cartographic modeling framework. As suggested in previous research, an area-based pycnophylactic interpolator is preferred to point interpolators in isopleth mapping not only because it preserves the total volume in each aggregation unit but also because it is non-parametric and is able to incorporate ancillary data to increase the accuracy of a surface representation. Here, a general pycnophylactic method is used to generate isopleth maps of density surfaces, but a hybrid approach is proposed to address the small denominator problem that arises when mapping ratio/rate and proportion/percentage surfaces. Finally, we propose a value-by-perspective height mapping procedure to resolve the visual equalization problem associated with ratio/rate and proportion/percentage surfaces that enable one to distinguish among high rate/large denominator, high rate/small denominator, low rate/large denominator, and low rate/small denominator regions of the surface.},
   number = {5},
   urldate = {2021-03-08},
@@ -327,8 +286,6 @@ @Article{lin_cartographic_2017
   author = {Jie Lin and Dean M. Hanink and Robert G. Cromley},
   month = {may},
   year = {2017},
-  note = {Publisher: Taylor \& Francis
-\_eprint: https://doi.org/10.1080/13658816.2016.1207776},
   keywords = {Cartographic modeling, isopleth mapping, pycnophylactic interpolation},
   pages = {849--866},
 }
@@ -338,8 +295,6 @@ @Article{galin_procedural_2010
   volume = {29},
   copyright = {© 2010 The Author(s) Journal compilation © 2010 The Eurographics Association and Blackwell Publishing Ltd.},
   issn = {1467-8659},
-  url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1467-8659.2009.01612.x},
-  doi = {10/cxvfkm},
   abstract = {In this paper, we propose an automatic method for generating roads based on a weighted anisotropic shortest path algorithm. Given an input scene, we automatically create a path connecting an initial and a final point. The trajectory of the road minimizes a cost function that takes into account the different parameters of the scene including the slope of the terrain, natural obstacles such as rivers, lakes, mountains and forests. The road is generated by excavating the terrain along the path and instantiating generic parameterized models.},
   language = {en},
   number = {2},
@@ -347,7 +302,6 @@ @Article{galin_procedural_2010
   journal = {Computer Graphics Forum},
   author = {E. Galin and A. Peytavie and N. Mar{\a'e}chal and E. Gu{\a'e}rin},
   year = {2010},
-  note = {\_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1467-8659.2009.01612.x},
   keywords = {Computer Graphics: Three-Dimensional Graphics and Realism, Procedural modeling, discrete anisotropic shortest path, road generation},
   pages = {429--438},
 }
@@ -356,7 +310,6 @@ @Article{hesselbarth_landscapemetrics_2019
   title = {landscapemetrics: an open-source {R} tool to calculate landscape metrics},
   volume = {42},
   shorttitle = {landscapemetrics},
-  doi = {10/gf4n9j},
   number = {10},
   journal = {Ecography},
   author = {Maximilian HK Hesselbarth and Marco Sciaini and Kimberly A. With and Kerstin Wiegand and Jakub Nowosad},
@@ -391,8 +344,6 @@ @Article{hirzel_which_2002
   title = {Which is the optimal sampling strategy for habitat suitability modelling},
   volume = {157},
   issn = {0304-3800},
-  url = {https://www.sciencedirect.com/science/article/pii/S030438000200203X},
-  doi = {10/ffpg65},
   abstract = {Designing an efficient sampling strategy is of crucial importance for habitat suitability modelling. This paper compares four such strategies, namely, ‘random’, ‘regular’, ‘proportional-stratified’ and ‘equal-stratified’—to investigate (1) how they affect prediction accuracy and (2) how sensitive they are to sample size. In order to compare them, a virtual species approach (Ecol. Model. 145 (2001) 111) in a real landscape, based on reliable data, was chosen. The distribution of the virtual species was sampled 300 times using each of the four strategies in four sample sizes. The sampled data were then fed into a GLM to make two types of prediction: (1) habitat suitability and (2) presence/absence. Comparing the predictions to the known distribution of the virtual species allows model accuracy to be assessed. Habitat suitability predictions were assessed by Pearson's correlation coefficient and presence/absence predictions by Cohen's κ agreement coefficient. The results show the ‘regular’ and ‘equal-stratified’ sampling strategies to be the most accurate and most robust. We propose the following characteristics to improve sample design: (1) increase sample size, (2) prefer systematic to random sampling and (3) include environmental information in the design.},
   language = {en},
   number = {2},
@@ -410,8 +361,6 @@ @Article{thomson_gridsample_2017
   volume = {16},
   issn = {1476-072X},
   shorttitle = {{GridSample}},
-  url = {https://doi.org/10.1186/s12942-017-0098-4},
-  doi = {10/gbqg4w},
   abstract = {Household survey data are collected by governments, international organizations, and companies to prioritize policies and allocate billions of dollars. Surveys are typically selected from recent census data; however, census data are often outdated or inaccurate. This paper describes how gridded population data might instead be used as a sample frame, and introduces the R GridSample algorithm for selecting primary sampling units (PSU) for complex household surveys with gridded population data. With a gridded population dataset and geographic boundary of the study area, GridSample allows a two-step process to sample “seed” cells with probability proportionate to estimated population size, then “grows” PSUs until a minimum population is achieved in each PSU. The algorithm permits stratification and oversampling of urban or rural areas. The approximately uniform size and shape of grid cells allows for spatial oversampling, not possible in typical surveys, possibly improving small area estimates with survey results.},
   number = {1},
   urldate = {2021-03-16},
@@ -427,8 +376,6 @@ @Article{holmes_problems_1967
   title = {Problems in {Location} {Sampling}},
   volume = {57},
   issn = {0004-5608},
-  url = {https://doi.org/10.1111/j.1467-8306.1967.tb00635.x},
-  doi = {10/cxsds3},
   abstract = {In geographical and related research uncertainty and error have arisen in the selection, application, and interpretation of designs in plane sampling largely through a failure to differentiate between area sampling and location sampling procedures. A survey of some commonly used area sampling designs indicates the frequency and extent of this error. Location sampling has remained a poorly understood technique through its confusion with area sampling, and there has been a consequent failure to grapple with the problems of stratifying by location when the primary sampling items are of varying areal extent or are irregularly spaced. An objective method of stratifying by location employing minimal aggregation is described and is used as a basis for both systematic and random samples. Tests on locationally stratified farm sample designs, based upon certain known and hypothetical farm characteristics in one New South Wales shire, indicate that increases in sampling precision obtained through locational stratification are directly related to the levels of spatial segregation in the items being sampled.},
   number = {4},
   urldate = {2021-03-16},
@@ -436,8 +383,6 @@ @Article{holmes_problems_1967
   author = {John Holmes},
   month = {dec},
   year = {1967},
-  note = {Publisher: Routledge
-\_eprint: https://doi.org/10.1111/j.1467-8306.1967.tb00635.x},
   pages = {757--780},
 }
 
@@ -446,8 +391,6 @@ @Article{boeing_spatial_2021
   volume = {56},
   issn = {0268-4012},
   shorttitle = {Spatial information and the legibility of urban form},
-  url = {https://www.sciencedirect.com/science/article/pii/S0268401219302154},
-  doi = {10/ggcg9v},
   abstract = {Urban planning and morphology have relied on analytical cartography and visual communication tools for centuries to illustrate spatial patterns, conceptualize proposed designs, compare alternatives, and engage the public. Classic urban form visualizations – from Giambattista Nolli’s ichnographic maps of Rome to Allan Jacobs’s figure-ground diagrams of city streets – have compressed physical urban complexity into easily comprehensible information artifacts. Today we can enhance these traditional workflows through the Smart Cities paradigm of understanding cities via user-generated content and harvested data in an information management context. New spatial technology platforms and big data offer new lenses to understand, evaluate, monitor, and manage urban form and evolution. This paper builds on the theoretical framework of visual cultures in urban planning and morphology to introduce and situate computational data science processes for exploring urban fabric patterns and spatial order. It demonstrates these workflows with OSMnx and data from OpenStreetMap, a collaborative spatial information system and mapping platform, to examine street network patterns, orientations, and configurations in different study sites around the world, considering what these reveal about the urban fabric. The age of ubiquitous urban data and computational toolkits opens up a new era of worldwide urban form analysis from integrated quantitative and qualitative perspectives.},
   language = {en},
   urldate = {2021-02-19},
@@ -463,8 +406,6 @@ @Article{orr_persistence_1969
   title = {The {Persistence} of the {Gerrymander} in {North} {Carolina} {Congressional} {Redistricting}},
   volume = {9},
   issn = {1549-6929},
-  url = {https://muse.jhu.edu/article/525615},
-  doi = {10/gh326j},
   abstract = {THE PERSISTENCE OF THE GERRYMANDER IN NORTH CAROLINA CONGRESSIONAL REDISTRICTING Douglas M. Orr, Jr.* One of the most important special geographic units below the state level is that established for conducting elections. The determination of one type of electoral unit, the congressional district, is a matter of considerable conse­ quence to our federal system of government as manifested in the United States House of Representatives—’’the grand depository of the democratic principle.” Yet in our supposedly democratic form of government, congres­ sional districts have traditionally been subject to enormous population disparities and gerrymandering. Political power is rarely surrendered volun­ tarily. A political “rule of the game” has been that the party or interest in power apportioned and redistricted so as to stay in power. North Carolina has been no exception. Among its 21 congressional district plans over the past 180 years, including three realignments since 1960, the gerrymander had helped perpetuate the rural domination of the state’s congressional delegation, and mor§ recently, it has been used to try to stem the rising tide of Republicanism and return Democratic incumbents to office. North Carolina therefore provides a meaningful case study as to the persistence of a tactic that has too long prevailed with the nation’s political system. GERRYMANDERING. The practice of gerrymandering actually began in Europe, but the term itself originated in 1812 in Massachusetts when Governor Elbridge Gerry carved out an electoral district that was said to resemble a salamander due to its winding shape (Fig. 1). The corruption of the two words gave American politics this descriptive term. This art of political cartography has not been confined to one group or region; both political parties in most parts of the country have practiced it. It represents the manipulation of district boundries in order to juggle district populations for partisan advantage. However, considerable misconception exists con­ cerning the gerrymander. A gerrymandered district may not always be identified by its shape, in spite of the common connotation of the term. The one vote requirement, for example, can be considered an “anti-gerrymandering ” development because it prevents the inequities of overpopulated and underpopulated districts which were motivated often by party strength in such districts. Yet population equality does not completely prevent gerry­ mandering, although it does restrict partisan maneuvering. The gerrymander may therefore be manifested in several forms, and this art of political abuse has become quite refined by more than a century of *Dr. Orr is assistant professor of geography at the University of North Carolina, Charlotte. The paper was accepted for publication in June 1969. 40 So u t h e a st e r n G e o g r a ph er application in American politics. The several major gerrymandering tech­ niques developed from this experience are summarized as follows: (1) 1. Stacked Districts—This type of gerrymandered district probably best fits the popular conception of the practice. The “stacked” district exhibits the grotesque shape that has inspired the many vivid district descriptions, as it winds its way across the landscape, seeking out pockets of voting strength of one party or interest in an overall area that is predominantly sympathetic to the opposition. Figure 1. The original gerrymander, as depicted in the Boston Gazette of March 26, 1812. The Massachusetts Legislature placed certain towns of Essex County into this odd­ shaped senatorial district in order to concentrate the Federalist vote in as few districts as possible. At firs t described as a salamander, it became known as a gerrymander because Governor Elbridge Gerry signed the redistricting bill into law. Source: Ruth C. Silva, {"}Reapportionm ent and Redistricting,” Scientific American, No. 5, November 1965, p. 21. Vol. IX, No. 2 41 2. Excess Votes.—A popular gerrymandering device is to concentrate the opposition’s vote in as few districts as possible so that it is squandered by “overkill.” Such planned landslides, also known as “packed” districts, insure safe constituencies for a party, but sacrifice votes that might be desperately needed in neighboring districts. Democrats are particularly susceptible to this technique because of the large concentration of traditionally Democratic voters in metropolitan areas. In the South, rural Democrats have “packed” districts against urban Democrats. 3. Wasted Votes.—This...},
   number = {2},
   urldate = {2021-02-07},
@@ -479,8 +420,6 @@ @Article{chou_taming_2006
   title = {Taming the {Gerrymander}—{Statistical} physics approach to {Political} {Districting} {Problem}},
   volume = {369},
   issn = {0378-4371},
-  url = {https://www.sciencedirect.com/science/article/pii/S0378437106001555},
-  doi = {10/fghzws},
   abstract = {The Political Districting Problem is mapped to a q-state Potts model in which the constraints can be written as interactions between sites or external fields acting on the system. Districting into q voter districts is equivalent to finding the ground state of this q-state Potts model. We illustrate this by districting Taipei city in its 2008 Legislature Election. Statistical properties of the model are also studied.},
   language = {en},
   number = {2},
@@ -497,8 +436,6 @@ @Article{honick_pictorial_1967
   title = {Pictorial {Navigation} {Displays}},
   volume = {4},
   issn = {0008-7041},
-  url = {https://doi.org/10.1179/caj.1967.4.2.72},
-  doi = {10/gh326k},
   abstract = {A pictorial navigation display for aircraft is described, in which the aircraft's ground position and track are continuously displayed, superimposed on the projected image in colour of a topographical map stored on microfilm. The microphotographic technique developed for preparation of the map films is also described. A navigation display of this type will be incorporated in the prototype Concorde supersonic airliner.},
   number = {2},
   urldate = {2021-02-06},
@@ -506,8 +443,6 @@ @Article{honick_pictorial_1967
   author = {K. R. Honick},
   month = {dec},
   year = {1967},
-  note = {Publisher: Taylor \& Francis
-\_eprint: https://doi.org/10.1179/caj.1967.4.2.72},
   pages = {72--81},
 }
 
@@ -515,8 +450,6 @@ @Article{ross_dicuil_2019
   title = {Dicuil (9th century) on triangular and square numbers},
   volume = {34},
   issn = {2637-5451},
-  url = {https://doi.org/10.1080/26375451.2019.1598687},
-  doi = {10/gh326m},
   abstract = {Dicuil was a ninth-century Irish monk who taught at the Carolingian school of Louis the Pious. He wrote a Computus or astronomical treatise in Latin in about 814–16, which contains a chapter on triangular and square numbers. Dicuil describes two methods for calculating triangular numbers: the simple method of summing the natural numbers, and the more complex method of multiplication, equivalent to the formula n(n + 1)/2. He also states that a square number is equal to twice a triangular number minus the generating number, equivalent to n2 = 2[n(n + 1)/2] – n. The multiplication formula for triangular numbers was first explicitly described in about the third century AD by the Greek authors Diophantus and Iamblichus. It was also known as a solution to other mathematical problems as early as 300 BC. It reappeared in the West in the sixteenth century. Dicuil thus fills a gap in our medieval knowledge.},
   number = {2},
   urldate = {2021-02-06},
@@ -524,14 +457,11 @@ @Article{ross_dicuil_2019
   author = {Helen Elizabeth Ross and Betty Irene Knott},
   month = {may},
   year = {2019},
-  note = {Publisher: Taylor \& Francis
-\_eprint: https://doi.org/10.1080/26375451.2019.1598687},
   pages = {79--94},
 }
 
 @Book{openshaw_modifiable_1983,
   title = {The modifiable areal unit problem},
-  url = {http://www.getcited.org/pub/102412488},
   publisher = {Geo Books Norwich,, UK},
   author = {Stan Openshaw},
   year = {1983},
@@ -541,8 +471,6 @@ @Article{mindell_exposure-based_2012
   title = {Exposure-{Based}, ‘{Like}-for-{Like}’ {Assessment} of {Road} {Safety} by {Travel} {Mode} {Using} {Routine} {Health} {Data}},
   volume = {7},
   issn = {1932-6203},
-  url = {http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0050606},
-  doi = {10.1371/journal.pone.0050606},
   abstract = {Background  Official reports on modal risk have not chosen appropriate numerators and denominators to enable like-for-like comparisons. We report age- and sex-specific deaths and injury rates from equivalent incidents in England by travel mode, distance travelled and time spent travelling.    Methods  Hospital admissions and deaths in England 2007–2009 were obtained for relevant ICD-10 external codes for pedestrians, cyclists, and car/van drivers, by age-group and sex. Distance travelled by age-group, sex and mode in England (National Travel Survey 2007–2009 data) was converted to time spent travelling using mean trip speeds. Fatality rates were compared with age-specific Netherlands data.    Results  All-age fatalities per million hours’ use (f/mhu) varied over the same factor-of-three range for both sexes (0.15–0.45 f/mhu by mode for men, 0.09–0.31 f/mhu for women). Risks were similar for men aged 21–49 y for all three modes and for female pedestrians and drivers aged 21–69 y. Most at risk were: males 17–20 y (1.3 f/mhu (95\% CI 1.2–1.4)) for driving; males 70+ (2.2 f/mhu(1.6–3.0)) for cycling; and females 70+ (0.95 f/mhu (0.86–1.1)) for pedestrians. In general, fatality rates were substantially higher among males than females. Risks per hour for male drivers \&lt;30 y were similar or higher than for male cyclists; for males aged 17–20 y, the risk was higher for drivers (33/Bn km (30–36), 1.3 f/mhu (1.2–1.4)) than cyclists (20/Bn km (10–37), 0.24 f/mhu (0.12–0.45)) whether using distance or time. Similar age patterns occurred for cyclists and drivers in the Netherlands. Age-sex patterns for injuries resulting in hospital admission were similar for cyclists and pedestrians but lower for drivers.    Conclusions  When all relevant ICD-10 codes are used, fatalities by time spent travelling vary within similar ranges for walking, cycling and driving. Risks for drivers were highest in youth and fell with age, while for pedestrians and cyclists, risks increased with age. For the young, especially males, cycling is safer than driving.},
   number = {12},
   urldate = {2016-03-10},