Freedman, D. S., & Mueller, E. (1974). Economic modules for use in fertility surveys in less developed countries. International Statistical Institute ; World Fertility Survey.
Chicago-referens (17:e uppl.)Freedman, Deborah S., och Eva Mueller. Economic Modules for Use in Fertility Surveys in Less Developed Countries. [Voorburg : London: International Statistical Institute ; World Fertility Survey, 1974.
MLA-referens (8:e uppl.)Freedman, Deborah S., och Eva Mueller. Economic Modules for Use in Fertility Surveys in Less Developed Countries. International Statistical Institute ; World Fertility Survey, 1974.
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