Center for International Earth Science Information Network (CIESIN), Columbia University; and Centro Internacional de Agricultura Tropical (CIAT). 2005. Gridded population of the world version 3 (GPWv3): National boundaries. Palisades, New York USA: Socioeconomic Data and Applications Center (SEDAC), Columbia University. Accessed 19 January 2007.
Resolution: 2.5 arc-minutes
Background: These global national boundaries are derived from the Gridded Population of the World (GPW) country-level land area grids. The list of countries and territories used follows that of the United Nations (UN), and in most cases the borders are from the Digital Chart of the World (DCW). Permanent ice and all but large lakes have been merged with neighboring polygons to make a layer more appropriate for cartographic visualization of the data. This layer does not include Antarctica.