Não informado. (1972). Current literature in family planning. Planned Parenthood Federation of America.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Current Literature in Family Planning. New York: Planned Parenthood Federation of America, 1972.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Current Literature in Family Planning. Planned Parenthood Federation of America, 1972.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.