Watt, L. (1929). Catholic social principles: A commentary on the papal encyclical Rerum novarum. Burns, Oates & Washbourne ltd..
Chicago-viite (17. p.)Watt, Lewis. Catholic Social Principles: A Commentary on the Papal Encyclical Rerum Novarum. London: Burns, Oates & Washbourne ltd., 1929.
MLA-viite (8. p.)Watt, Lewis. Catholic Social Principles: A Commentary on the Papal Encyclical Rerum Novarum. Burns, Oates & Washbourne ltd., 1929.
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