APA
United Nations. Department of International Economic and Social Affairs, . (1991). Concise report on the world population situation in 1991. New York: United Nations.
Chicago
United Nations. Department of International Economic and Social Affairs, . 1991. Concise report on the world population situation in 1991. New York: United Nations.
Harvard
United Nations. Department of International Economic and Social Affairs, . (1991). Concise report on the world population situation in 1991. New York: United Nations.
MLA
United Nations. Department of International Economic and Social Affairs, . Concise report on the world population situation in 1991. New York: United Nations. 1991.