Natividad, J. N., & Kabamalan, M. M. M. (2012). Responsible parenthood: Natural family planning program in the regions : 2010. Commission on Population.
Chicago-viite (17. p.)Natividad, Josefina N., ja Maria Midea M. Kabamalan. Responsible Parenthood: Natural Family Planning Program in the Regions : 2010. Mandaluyong City: Commission on Population, 2012.
MLA-viite (9. p.)Natividad, Josefina N., ja Maria Midea M. Kabamalan. Responsible Parenthood: Natural Family Planning Program in the Regions : 2010. Commission on Population, 2012.
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