Pius XII, P. (1956). Psychological method of natural painless childbirth: Address. National Catholic Welfare Conference.
Chicago-viite (17. p.)Pius XII, Pope. Psychological Method of Natural Painless Childbirth: Address. Washington: National Catholic Welfare Conference, 1956.
MLA-viite (8. p.)Pius XII, Pope. Psychological Method of Natural Painless Childbirth: Address. National Catholic Welfare Conference, 1956.
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