Casanova, Robert; Weiss, Patrice M. Beckmann and Ling's obstetrics and gynecology. Casanova, Robert,, Chuang, Alice,, Goepfert, Alice R.,, Hueppchen, Nancy A.,, Weiss, Patrice M.,, American College of Obstetricians and Gynecologists 8th. Philadelphia. April 2018. ISBN 978-1-4963-5309-2. OCLC 949870151.