Udhibiti wa uzazi
Stubblefield, Phillip G.; Roncari, Danielle M. (December 12, 2011). "Family Planning", pp. 211–269, in Berek, Jonathan S. (ed.) Berek & Novak's Gynecology, 15th ed. Philadelphia: Lippincott Williams & Wilkins, ISBN 978-1-4511-1433-1.