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-referens (17:e uppl.)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-referens (8:e uppl.)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.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.