Catholic Church. Pope (1922-1939 : Pius XI), Pius, X., & Treacy, G. C. (1930). Christian education of youth: Encyclical letter. Paulist Press.
Lua i Stíl Chicago (17ú heag.)Catholic Church. Pope (1922-1939 : Pius XI), XI Pius, agus Gerald C. Treacy. Christian Education of Youth: Encyclical Letter. New York, N.Y.: Paulist Press, 1930.
Lua MLA (8ú heag.)Catholic Church. Pope (1922-1939 : Pius XI), et al. Christian Education of Youth: Encyclical Letter. Paulist Press, 1930.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.