1. Sexual and contraceptive experience of young unmarried women in the United States, 1976 and 1971;Zelnik;Fam Plann Perspect,1977
2. 3. Abortion Surveillance, Annual Summary. Atlanta, Center for Disease Control, Dept HEW, 1976, 1978, Table 6.
3. 4. Final Natality Statistics. National Center for Health Statistics, Dept HEW, 1977, Hyattsville, Maryland, 1979, Tables 2, 13.
4. 5. Facts About Venereal Disease. Atlanta, Center for Disease Control, Dept HEW, 1976, pp 3, 8.