APA (7th ed.) Citation

Waley, D. P. (1961). The Papal State in the thirteenth century. Macmillan.

Chicago Style (17th ed.) Citation

Waley, Daniel Philip. The Papal State in the Thirteenth Century. London: Macmillan, 1961.

MLA (9th ed.) Citation

Waley, Daniel Philip. The Papal State in the Thirteenth Century. Macmillan, 1961.