Leo XIII, P. C. C. P. (1939). Rerum Novarum, Encyclical Letter of pope Leo XIII on the Condition of Labor. New York.
Chicago-viite (17. p.)Leo XIII, Pope; Catholic Church. Pope. Rerum Novarum, Encyclical Letter of Pope Leo XIII on the Condition of Labor. New York, 1939.
MLA-viite (8. p.)Leo XIII, Pope; Catholic Church. Pope. Rerum Novarum, Encyclical Letter of Pope Leo XIII on the Condition of Labor. New York, 1939.
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