APA (7th ed.) Citation

Duffy, E. (2011). Ten popes who shook the world. Yale University Press.

Chicago Style (17th ed.) Citation

Duffy, Eamon. Ten Popes Who Shook the World. New Haven: Yale University Press, 2011.

MLA (9th ed.) Citation

Duffy, Eamon. Ten Popes Who Shook the World. Yale University Press, 2011.

Warning: These citations may not always be 100% accurate.