APA (7th ed.) Citation

Humble, R. (1993). English castles. Artus Bks.

Chicago Style (17th ed.) Citation

Humble, Richard. English Castles. London: Artus Bks, 1993.

MLA (9th ed.) Citation

Humble, Richard. English Castles. Artus Bks, 1993.

Warning: These citations may not always be 100% accurate.