Não informado. (2002). ACOG Practice Bulletin. American College of Obstetricians and Gynecologists.
Chicago-viite (17. p.)Não informado. ACOG Practice Bulletin. Washington: American College of Obstetricians and Gynecologists, 2002.
MLA-viite (8. p.)Não informado. ACOG Practice Bulletin. American College of Obstetricians and Gynecologists, 2002.
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