APA
United Nations. Department of International Economic and Social Affairs, . (1990). Stable population age distribution. New york: United Nations.
Chicago
United Nations. Department of International Economic and Social Affairs, . 1990. Stable population age distribution. New york: United Nations.
Harvard
United Nations. Department of International Economic and Social Affairs, . (1990). Stable population age distribution. New york: United Nations.
MLA
United Nations. Department of International Economic and Social Affairs, . Stable population age distribution. New york: United Nations. 1990.