Não informado. (1976). Advance Data from Vital & Health Statistics. National Center for Health Statistics.
Chicago-viite (17. p.)Não informado. Advance Data from Vital & Health Statistics. Hyattsville, Md: National Center for Health Statistics, 1976.
MLA-viite (8. p.)Não informado. Advance Data from Vital & Health Statistics. National Center for Health Statistics, 1976.
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