Cita APA (7a ed.)

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

Cita Chicago Style (17a ed.)

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

Cita MLA (9a ed.)

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