Não informado. (1980). Postgraduate Obstetrics & Gynecology. Postgraduate Obstetrics & Gynecology.
Chicago-referens (17:e uppl.)Não informado. Postgraduate Obstetrics & Gynecology. Philadelphia, Pa: Postgraduate Obstetrics & Gynecology, 1980.
MLA-referens (8:e uppl.)Não informado. Postgraduate Obstetrics & Gynecology. Postgraduate Obstetrics & Gynecology, 1980.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.