How to create thiessen polygons from points using R packages?

Question

I have multiple sets of points (for different years ~20)

I want to generate thiessen polygons for each set of points using r spatial packages.

I know this c

Answer 1

Same principle as shown by jbaums, but simpler code:

library(dismo)
library(rgdal)
cities <- shapefile(file.path(system.file("vectors", package = "rgdal")[1], "cities"))

v <- voronoi(cities)
plot(v)