Cita APA (7a ed.)
Thornbury, W. D. (1969). Principles of geomorphology (2d ed.). New Age International.
Cita Chicago Style (17a ed.)
Thornbury, William D. Principles of Geomorphology. 2d ed. New Delhi: New Age International, 1969.
Cita MLA (9a ed.)
Thornbury, William D. Principles of Geomorphology. 2d ed. New Age International, 1969.
Precaución: Estas citas no son 100% exactas.