APA (7th ed.) Citation

Archer, P. (1941). The Christian calendar and the Gregorian reform. Fordham university press.

Chicago Style (17th ed.) Citation

Archer, Peter. The Christian Calendar and the Gregorian Reform. New York: Fordham university press, 1941.

MLA (9th ed.) Citation

Archer, Peter. The Christian Calendar and the Gregorian Reform. Fordham university press, 1941.