Gaya APA

Ullmann, W. (1975). Law and politics in the Middle Ages. An introd. to the sources of medieval political ideas. - The Sources of History: Studies in the uses of historical evidence. . London: Sources of History Ltd.

Gaya MLA

Ullmann, Walter. "Law and politics in the Middle Ages. An introd. to the sources of medieval political ideas. - The Sources of History: Studies in the uses of historical evidence. ". London: Sources of History Ltd, 1975. Buku.