ack MachineUnderpopulation? MercatorNetUnited Nations (2004). Population Division, Department of Economic and Social Affairs. Retrieved February 13, 2004.United Nations Economic Commission for Europe - Official Web SiteUnited States Census Bureau (2005). Census Bureau - Countries Ranked by Population. Retrieved February 13, 2005.World Population Counter, and separate regions.WorldPopClock.com. (French)Populations du monde. (French)OECD population data[permanent dead link]vteලෝක ජනගහනයMajor topicsBiocapacityOptimum populationOverpopulationMalthusian catastrophePopulationPopulation ethicsPopulation momentumSustainable developmentWomen's reproductive rightsZero population growthBiological andrelated topicsFamily planningPledge two or fewerHuman population planningOne-child policyTwo-child policyPopulation biologyPopulation declinePopulation densityPhysiological densityPopulation dynamicsPopulation growthPopulation modelPopulation pyramidProjections of pop