APA (7e ed.) Bronvermelding

Cheetham, N. Keepers of the keys: A history of the Popes from St. Peter to John Paul II.

Chicago (17e ed.) Bronvermelding

Cheetham, Nicolas. Keepers of the Keys: A History of the Popes from St. Peter to John Paul II.

MLA (8e ed.) Bronvermelding

Cheetham, Nicolas. Keepers of the Keys: A History of the Popes from St. Peter to John Paul II.

Let op: Deze citaties zijn niet altijd 100% accuraat.