APA (7th ed.) Citation

Ruhlen, M. (1987). A guide to the world's languages. E. Arnold.

Chicago Style (17th ed.) Citation

Ruhlen, Merritt. A Guide to the World's Languages. London: E. Arnold, 1987.

MLA (9th ed.) Citation

Ruhlen, Merritt. A Guide to the World's Languages. E. Arnold, 1987.

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