United Nations Department of International Economic and Social Affairs. (1991). Concise report on the world population situation in 1991, with a special emphasis on age structure. United Nations.
Chicago-viite (17. p.)United Nations Department of International Economic and Social Affairs. Concise Report on the World Population Situation in 1991, with a Special Emphasis on Age Structure. New York: United Nations, 1991.
MLA-viite (9. p.)United Nations Department of International Economic and Social Affairs. Concise Report on the World Population Situation in 1991, with a Special Emphasis on Age Structure. United Nations, 1991.
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