Research Conference on Natural Family Planning, W., Urichie, W. A., & Natural family planning. (1973). Proceedings. Human Life Foundations.
Chicago-viite (17. p.)Research Conference on Natural Family Planning, Warrenton, William A. Urichie, ja Natural family planning. Proceedings. Washington, D. C: Human Life Foundations, 1973.
MLA-viite (9. p.)Research Conference on Natural Family Planning, Warrenton, et al. Proceedings. Human Life Foundations, 1973.
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