R (>= 2.10), ggplot2, RColorBrewer, rgdal, grid
R (>= 2.10), ggplot2, maptools, RColorBrewer, rgdal, grid
R (>= 2.10), maptools, RColorBrewer, rgdal, sp
R (>= 3.5), maptools, RColorBrewer, rgdal, sp
R (>= 3.5), maptools, RColorBrewer, rgdal, sp, sf
ggplot2, grid, maptools, RColorBrewer, rgdal