Periodic abstinence
Card's contents:POPULATION REPORTS SER. I 295,479 PERIODIC Periodic abstinence. Washington 4° The Population Information Program The George Washington Univ. Medical Center Population Reports ser. I Nr 1. Birth control without contraceptives. 1974. s. 19, il. Nr 2. Sex preselection, not yet practical. 1975. s. 21- 32, il.