United Nations, D. o. E. a. S. A. (1970). Variables and questionaire for comparative fertility surveys: (Population Studies No. 45). United Nations.
Cita Chicago (17th ed.)United Nations, Dept. of Economic and Social Affairs. Variables and Questionaire for Comparative Fertility Surveys: (Population Studies No. 45). New York: United Nations, 1970.
Cita MLA (9th ed.)United Nations, Dept. of Economic and Social Affairs. Variables and Questionaire for Comparative Fertility Surveys: (Population Studies No. 45). United Nations, 1970.
Atenció: Aquestes cites poden no estar 100% correctes.