Não informado. (2002). ACOG educational bulletin. American College of Obstetricians and Gynecologists.
Chicago-referens (17:e uppl.)Não informado. ACOG Educational Bulletin. Washington: American College of Obstetricians and Gynecologists, 2002.
MLA-referens (8:e uppl.)Não informado. ACOG Educational Bulletin. American College of Obstetricians and Gynecologists, 2002.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.