APA (7e ed.) Bronvermelding

Ullmann, W. (1965). A history of political thought: The middle ages. Penguin.

Chicago (17e ed.) Bronvermelding

Ullmann, Walter. A History of Political Thought: The Middle Ages. Harmondsworth: Penguin, 1965.

MLA (9e ed.) Bronvermelding

Ullmann, Walter. A History of Political Thought: The Middle Ages. Penguin, 1965.