Catholic Church. Pope. (1891). Encyclical letter of our Holy Father by divine providence Pope Leo XIII on the condition of labor. Official translation. Baltimore : John Murphy & Co..
Chicago-viite (17. p.)Catholic Church. Pope. Encyclical Letter of Our Holy Father by Divine Providence Pope Leo XIII on the Condition of Labor. Official Translation. Baltimore : John Murphy & Co., 1891.
MLA-viite (8. p.)Catholic Church. Pope. Encyclical Letter of Our Holy Father by Divine Providence Pope Leo XIII on the Condition of Labor. Official Translation. Baltimore : John Murphy & Co., 1891.
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