Style de citation APA (7e éd.)

Heywood, W., & Douglas, R. L. (1910). A History of Perugia: With twenty one illustrations. Methuen & Co..

Style de citation Chicago (17e éd.)

Heywood, William, et R. Langton Douglas. A History of Perugia: With Twenty One Illustrations. London: Methuen & Co., 1910.

Style de citation MLA (9e éd.)

Heywood, William, et R. Langton Douglas. A History of Perugia: With Twenty One Illustrations. Methuen & Co., 1910.