APA (7th ed.) Citation

Warre, W., Warre, E., & Warre, W. A. (1999). Letters from the Peninsula, 1808-1812. Spellmount [etc.].

Chicago Style (17th ed.) Citation

Warre, William, Edmond Warre, and William Acheson Warre. Letters from the Peninsula, 1808-1812. Staplehurst: Spellmount [etc.], 1999.

MLA (9th ed.) Citation

Warre, William, et al. Letters from the Peninsula, 1808-1812. Spellmount [etc.], 1999.