Leo XIII, P. C. C. P. (1902). Encyclical Letter of Our Holy Father by Divine Providence Pope Leo XIII on the Condition of Labor. Brooklyn.
Παραπομπή σε μορφή Chicago (17η εκδ.)Leo XIII, Pope; Catholic Church. Pope. Encyclical Letter of Our Holy Father by Divine Providence Pope Leo XIII on the Condition of Labor. Brooklyn, 1902.
Παραπομπή σε μορφή MLA (8th εκδ.)Leo XIII, Pope; Catholic Church. Pope. Encyclical Letter of Our Holy Father by Divine Providence Pope Leo XIII on the Condition of Labor. Brooklyn, 1902.
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