Catholic Church. Pope (1878-1903 : Leo XIII), Catholic Church. Pope (1922-1939 : Pius XI), & Husslein, J. (1940). Social wellsprings: Fourteen Epochal Documents. The Bruce publishing company.
Chicago-viite (17. p.)Catholic Church. Pope (1878-1903 : Leo XIII), Catholic Church. Pope (1922-1939 : Pius XI), ja Joseph Husslein. Social Wellsprings: Fourteen Epochal Documents. Milwaukee: The Bruce publishing company, 1940.
MLA-viite (8. p.)Catholic Church. Pope (1878-1903 : Leo XIII), et al. Social Wellsprings: Fourteen Epochal Documents. The Bruce publishing company, 1940.
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