APA
United Nations E. a. S. A. o. O., United Nations E. a. S. A. o. O., . (1972). Statistical yearbook 1971. : .
Chicago
United Nations Economic and Social Affairs(Deptt of-),Statistical Office, United Nations Economic and Social Affairs(Deptt of-),Statistical Office, . 1972. Statistical yearbook 1971. : .
Harvard
United Nations E. a. S. A. o. O., United Nations E. a. S. A. o. O., . (1972). Statistical yearbook 1971. : .
MLA
United Nations Economic and Social Affairs(Deptt of-),Statistical Office, United Nations Economic and Social Affairs(Deptt of-),Statistical Office, . Statistical yearbook 1971. : . 1972.
