Pius XII, P. (1956). Psychological method of natural painless childbirth: Address. National Catholic Welfare Conference.
Lua i Stíl Chicago (17ú heag.)Pius XII, Pope. Psychological Method of Natural Painless Childbirth: Address. Washington: National Catholic Welfare Conference, 1956.
Lua MLA (8ú heag.)Pius XII, Pope. Psychological Method of Natural Painless Childbirth: Address. National Catholic Welfare Conference, 1956.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.