APA (7e ed.) Bronvermelding

THORNBURY, W. D. (1969). Principles of geomorphology.-- Ed.2. John Wiley and Sons.

Chicago (17e ed.) Bronvermelding

THORNBURY, William D. Principles of Geomorphology.-- Ed.2. New York: John Wiley and Sons, 1969.

MLA (9e ed.) Bronvermelding

THORNBURY, William D. Principles of Geomorphology.-- Ed.2. John Wiley and Sons, 1969.