Leo XIII, P. C. C. P. (1924). Encyclical Letter on the Condition of Labor. Brooklyn.
Chicago-viite (17. p.)Leo XIII, Pope; Catholic Church. Pope. Encyclical Letter on the Condition of Labor. Brooklyn, 1924.
MLA-viite (8. p.)Leo XIII, Pope; Catholic Church. Pope. Encyclical Letter on the Condition of Labor. Brooklyn, 1924.
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