APA
UNITED NATIONS I. N. C., . (1972). Statistics on narcotic drugs for 1971 and Maximum levels of opium stocks. New York: United Nations.
Chicago
UNITED NATIONS INTERNATIONAL NARCOTICS CONTROL(Board), . 1972. Statistics on narcotic drugs for 1971 and Maximum levels of opium stocks. New York: United Nations.
Harvard
UNITED NATIONS I. N. C., . (1972). Statistics on narcotic drugs for 1971 and Maximum levels of opium stocks. New York: United Nations.
MLA
UNITED NATIONS INTERNATIONAL NARCOTICS CONTROL(Board), . Statistics on narcotic drugs for 1971 and Maximum levels of opium stocks. New York: United Nations. 1972.
