APA (7th ed.) Citation

Thornbury, W. D. (1968). Principles of geomorphology (2d ed.). Wiley.

Chicago Style (17th ed.) Citation

Thornbury, William D. Principles of Geomorphology. 2d ed. New York: Wiley, 1968.

MLA (9th ed.) Citation

Thornbury, William D. Principles of Geomorphology. 2d ed. Wiley, 1968.