Cita APA (7a ed.)

Hebblethwaite, P. (1978). The year of three popes. Collins.

Cita Chicago Style (17a ed.)

Hebblethwaite, Peter. The Year of Three Popes. London [etc.]: Collins, 1978.

Cita MLA (9a ed.)

Hebblethwaite, Peter. The Year of Three Popes. Collins, 1978.