Contraceptive Sterilization and Professional Natural Family Planning Education

Pope Paul V.I. , Humanae Vitae, An Encyclical Letter. July 25, 1968. Paragraph 14.

Pope Paul V.I. , Humanae Vitae, An Encyclical Letter. July 25, 1968, Paragraph 15.

Ethical and Religious Directives for Catholic Health Care Services. National Conference of Catholic Bishops. November 1995 (see Origins, Vol. 24, No. 27, December 15, 1995).

Code of Ethics, American Academy of Natural Family Planning, St. Louis, Missouri, 1983.

National Standards for Natural Family Planning. National Conference of Catholic Bishops, United States Catholic Confereence 1990, p. 11.