APA استشهاد

Curtis, E. (1912). Roger of Sicily and the Normans in Lower Italy, 1016-1154. New York ; London: G. P. Putnam's Sons.

استشهاد بنمط شيكاغو

Curtis, Edmund. Roger of Sicily and the Normans in Lower Italy, 1016-1154. New York ; London: G. P. Putnam's Sons, 1912.

MLA استشهاد

Curtis, Edmund. Roger of Sicily and the Normans in Lower Italy, 1016-1154. New York ; London: G. P. Putnam's Sons, 1912.