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.
Background: 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).