1. United States Food and Drug Administration. Norplant System (Levonorgestrel Implants): Prescribing Information. Washington, DC: United States Food and Drug Administration, 1990.
2. Norplant contraceptive subdermal implants,1990
3. Sustained-release contraceptives;Darney;Curr Probl Obstet Gynecol Fertil,1990
4. The “U” technique;Praptohardjo;Contraception,1993
5. The Emory Method;Sarma;Contraception,1994