Population Reference Bureau
A research organization that publishes research papers and data relating to reproductive health, children and families, population and environment, and other population issues.
United Nations Population Division
Many of the Population Division's publications are available as free downloads via this website. The Population Database provides historical, current and forecast population statistics. The World Migrant Stock database has both current and historical immigration and refugee statistics.
United Nations Population Fund (UNFPA)
News and publications of the UNFPA, including the annual publication State of World Population.