Cita APA (7a ed.)

Coppa, F. J. (1979). Pope Pius ix: Crusader in a secular age. Twayne.

Cita Chicago Style (17a ed.)

Coppa, Frank J. Pope Pius Ix: Crusader in a Secular Age. Boston: Twayne, 1979.

Cita MLA (9a ed.)

Coppa, Frank J. Pope Pius Ix: Crusader in a Secular Age. Twayne, 1979.

Precaución: Estas citas no son 100% exactas.