Treacy, G. C. L. X. (1941). Christian democracy, encyclical letter of Pope Leo XIII. Graves de communi. With Discussion Club Outline by Rev. Gerald C. Treacy, S.J. New York.
Chicago-viite (17. p.)Treacy, Gerald C.; Leo XIII. Christian Democracy, Encyclical Letter of Pope Leo XIII. Graves De Communi. With Discussion Club Outline by Rev. Gerald C. Treacy, S.J. New York, 1941.
MLA-viite (8. p.)Treacy, Gerald C.; Leo XIII. Christian Democracy, Encyclical Letter of Pope Leo XIII. Graves De Communi. With Discussion Club Outline by Rev. Gerald C. Treacy, S.J. New York, 1941.
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