Demacopoulos, G. E. (2015). Gregory the Great: Ascetic, pastor, and first man of Rome. University of Notre Dame Press.
Chicago-referens (17:e uppl.)Demacopoulos, George E. Gregory the Great: Ascetic, Pastor, and First Man of Rome. Notre Dame, Indiana: University of Notre Dame Press, 2015.
MLA-referens (9:e uppl.)Demacopoulos, George E. Gregory the Great: Ascetic, Pastor, and First Man of Rome. University of Notre Dame Press, 2015.
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