1. Multicenter trial of a monophasic oral contraceptive containing ethinyl estradiol and desogestrel;Rekers;Acta Obstet Gynecol Scand,1988
2. Multicentre study with a new biphasic oral contraceptive containing ethinylestradiol and desogestrel. Report on efficacy, cycle control and adverse experiences with special emphasis on blood pressure and weight;Dieben;Arzneimittelforschung,1991
3. A multicenter comparative trial of triphasic and monophasic, low-dose combined oral contraceptives;Dunson;Contraception,1993
4. Multicenter randomized comparative trial of two low-dose triphasic combined oral contraceptives containing desogestrel or norethindrone;Shoupe;Obstet Gynecol,1994
5. Efficacy, cycle control, and safety of two triphasic oral contraceptives;Kaunitz;Contraception,2000