Cheetham, N. Keepers of the keys: A history of the Popes from St. Peter to John Paul II.
Chicago-viite (17. p.)Cheetham, Nicolas. Keepers of the Keys: A History of the Popes from St. Peter to John Paul II.
MLA-viite (8. p.)Cheetham, Nicolas. Keepers of the Keys: A History of the Popes from St. Peter to John Paul II.
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