Catholic Church. Pope (1878-1903 : Leo XIII) & Treacy, G. C. (1941). Christian democracy: Encyclical letter of Pope Leo XIII. Graves de communi. The Paulist Press.
Chicago-viite (17. p.)Catholic Church. Pope (1878-1903 : Leo XIII) ja Gerald C. Treacy. Christian Democracy: Encyclical Letter of Pope Leo XIII. Graves De Communi. New York: The Paulist Press, 1941.
MLA-viite (8. p.)Catholic Church. Pope (1878-1903 : Leo XIII) ja Gerald C. Treacy. Christian Democracy: Encyclical Letter of Pope Leo XIII. Graves De Communi. The Paulist Press, 1941.
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