APA (7th ed.) Citation

Guinness, D., & Ryan, W. (1971). Irish houses & castles. Viking Press.

Chicago Style (17th ed.) Citation

Guinness, Desmond, and William Ryan. Irish Houses & Castles. New York: Viking Press, 1971.

MLA (9th ed.) Citation

Guinness, Desmond, and William Ryan. Irish Houses & Castles. Viking Press, 1971.