APA (7th ed.) Citation

Ruhlen, M. (1991). A guide to the world's languages. Stanford University Press.

Chicago Style (17th ed.) Citation

Ruhlen, Merritt. A Guide to the World's Languages. Stanford, Calif.: Stanford University Press, 1991.

MLA (9th ed.) Citation

Ruhlen, Merritt. A Guide to the World's Languages. Stanford University Press, 1991.