1. Armijo, R., & Monreal, T. Epidemiology of provoked abortion in Santiago, Chile.Journal of Sex Research 1965,1 143?159.
2. Back, K.W., & Hass, P.H. Family structure and fertility control. In J.T. Fawcett (Ed.),Psychological perspectives on population. New York: Basic Books, 1973.
3. Bamberger, M., & Earle, M. Factors affecting the success of a family planning program in a low-income neighborhood in Caracas.Studies in Family Planning 1971,2 175?178.
4. Blake, J.Family structure in Jamaica. New York: Free Press, 1961.
5. Blood, R.O., & Wolfe, D.M.Husbands and wives: The dynamics of married living. Glencoe, Illinois: Free Press, 1960.