United Nations. Department of International Economic and Social Affairs. (1983). Fertility levels and trends as assessed from twenty world fertility surveys. United Nations.
Chicago-viite (17. p.)United Nations. Department of International Economic and Social Affairs. Fertility Levels and Trends as Assessed from Twenty World Fertility Surveys. New York: United Nations, 1983.
MLA-viite (9. p.)United Nations. Department of International Economic and Social Affairs. Fertility Levels and Trends as Assessed from Twenty World Fertility Surveys. United Nations, 1983.
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