Catholic Church. Pope (1922-1939 : Pius XI) & Treacy, G. C. Atheistic communism: Encyclical letter of His Holiness Pope Pius XI (with discussion club outline). Paulist Press.
Chicago-viite (17. p.)Catholic Church. Pope (1922-1939 : Pius XI) ja Gerald C. Treacy. Atheistic Communism: Encyclical Letter of His Holiness Pope Pius XI (with Discussion Club Outline). New York: Paulist Press.
MLA-viite (8. p.)Catholic Church. Pope (1922-1939 : Pius XI) ja Gerald C. Treacy. Atheistic Communism: Encyclical Letter of His Holiness Pope Pius XI (with Discussion Club Outline). Paulist Press.
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