APA (7th ed.) Citation

Catholic Church. Pope (1922-1939 : Pius XI). (1970). Encyclical letter (Divini illius magistri). Catholic Truth Society.

Chicago Style (17th ed.) Citation

Catholic Church. Pope (1922-1939 : Pius XI). Encyclical Letter (Divini Illius Magistri). London: Catholic Truth Society, 1970.

MLA (8th ed.) Citation

Catholic Church. Pope (1922-1939 : Pius XI). Encyclical Letter (Divini Illius Magistri). Catholic Truth Society, 1970.

Warning: These citations may not always be 100% accurate.