1. Recommendations on oral contraception. 18th Meeting of the “Zürcher Gesprächskreis” April 1997;Bettendorf;Der Frauenarzt,1997
2. Hirsutismus;Breckwoldtt,1989
3. Hirsutism;Breckwoldtt,1990
4. Contraception and fertility in 2000 women;Pearl;Human Biol,1932
5. Application of life table techniques to measurement of contraceptive effectiveness;Potter;Demography,1966