Cita APA (7a ed.)

Willis, G. G. (1994). A history of early Roman liturgy to the death of Pope Gregory the Great. Boydell Press.

Cita Chicago Style (17a ed.)

Willis, Geoffrey Grimshaw. A History of Early Roman Liturgy to the Death of Pope Gregory the Great. Woodbridge [Suffolk]: Boydell Press, 1994.

Cita MLA (9a ed.)

Willis, Geoffrey Grimshaw. A History of Early Roman Liturgy to the Death of Pope Gregory the Great. Boydell Press, 1994.