APA-viite (7. p.)
Ullmann, W. (1966). Principles of government and politics in the Middle Ages (2 ed.). Methuen.
Chicago-viite (17. p.)
Ullmann, Walter. Principles of Government and Politics in the Middle Ages. 2 ed. London: Methuen, 1966.
MLA-viite (9. p.)
Ullmann, Walter. Principles of Government and Politics in the Middle Ages. 2 ed. Methuen, 1966.
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