Pius, P. C. C. P. (1939). Summi Pontificatus, The First Encyclical of Pope Pius XII on the Need For Unity in Society. S.l..
Chicago-viite (17. p.)Pius, Pope; Catholic Church. Pope. Summi Pontificatus, The First Encyclical of Pope Pius XII on the Need For Unity in Society. S.l., 1939.
MLA-viite (8. p.)Pius, Pope; Catholic Church. Pope. Summi Pontificatus, The First Encyclical of Pope Pius XII on the Need For Unity in Society. S.l., 1939.
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