1. Test kits for ovulation and pregnancy;Batzer;Technology 1987: Contemporary OB/GYN.,1986
2. Task force on methods for the determination of the fertile period;Am J Obstet Gynecol.,1980
3. The Ovulation Method of AJFP;Hilgers,1982
4. Natural family planning I: The peak symptom and estimated time of ovulation;Hilgers;Obstet Gynecol.,1978
5. Prediction and detection of ovulation;Moghissi;Fertil Steril.,1980