Citazione Stile APA (7a Edizione)

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

Citazione stile Chigago Style (17a edizione)

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

Citatione MLA (9a ed.)

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