1. Chesler, E. (1992) Woman of Valor. Margaret Sanger and the Birth Control Movement in America, p.36, Simon & Schuster; Noonan, J.T. (1965) Contraception. A History of Its Treatment by the Catholic Theologians and Canonists, pp. 438–442, Harvard University Press.
2. Hartman, C. (1936) Time of Ovulation in Women. A Study on the Fertile Period in the Menstrual Cycle, p. 117, William & Wilkins.
3. The ‘safe period’ as a birth control measure. A study and evaluation of available data;Dickinson;Am. J. Obstet. Gynecol.,1927
4. The birth control debate reached all sections of society through the media, which were divided on the matter. Sampling of popular magazines between 1920 and 1940 shows that the numerous socioeconomic, demographic, eugenic, medical and moral arguments for and against contraception overlapped, making an informed decision whether to use birth control a difficult one. See Viterbo, P. (2000) The Promise of Rhythm: The Determination of the Woman's Time of Ovulation and its Social Impact in the United States, 1920–1940, pp. 115–215, Doctoral Dissertation, SUNY, Stony Brook.
5. Birth control as seen by a mother;McNeely;Outlook,1928