APA (7th ed.) Citation

Sybel, H. v., & Duff Gordon, L. (1861). The history and literature of the Crusades. Chapman and Hall.

Chicago Style (17th ed.) Citation

Sybel, Heinrich von, and Lucie Duff Gordon. The History and Literature of the Crusades. London: Chapman and Hall, 1861.

MLA (8th ed.) Citation

Sybel, Heinrich von, and Lucie Duff Gordon. The History and Literature of the Crusades. Chapman and Hall, 1861.