Gilson, E. (1957). The church speaks to the modern world The social teachings of Leo XIII (4ª ed.). Image Books.
Chicago-viite (17. p.)Gilson, Etienne. The Church Speaks to the Modern World The Social Teachings of Leo XIII. 4ª ed. Image Books, 1957.
MLA-viite (9. p.)Gilson, Etienne. The Church Speaks to the Modern World The Social Teachings of Leo XIII. 4ª ed. Image Books, 1957.
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