Gaya APA
Duffy, E. (1997).
Saints & sinners: A history of the popes. .
New Haven & London:
New Haven & London Yale University Press.
Gaya MLA
Duffy, Eamon.
"Saints & sinners: A history of the popes. ".
New Haven & London:
New Haven & London Yale University Press,
1997.
Buku.