1. The misplaced or missing IUD;Gentile;Obset Gynecol Survey,1977
2. Complete and partial uterine perforation and embedding following insertion of intrauterine devices. II. Diagnosis methods, prevention and management;Zakin;Obstet Gynecol Survey,1981
3. Mechanism of action, safety and efficacy of intrauterine devices;WHO,1987
4. Scheme for management of “lost” IUD threads;Guillebaud;IPPF Medical Bulletin,1980
5. International Medical Advisory Panel Meetings (IPPF);International Planned Parenthood (IPPF),1987