APA (7th ed.) Citation

Gascoigne, C., & Gascoigne, B. (1975). Castles of Britain. Putnam.

Chicago Style (17th ed.) Citation

Gascoigne, Christina, and Bamber Gascoigne. Castles of Britain. New York: Putnam, 1975.

MLA (9th ed.) Citation

Gascoigne, Christina, and Bamber Gascoigne. Castles of Britain. Putnam, 1975.