Thornbury, W. D. (1969). Principles Geomorphology. Wiley.
Chicago Style (17th ed.) ZitazioaThornbury, William David. Principles Geomorphology. New York: Wiley, 1969.
MLA (9th ed.) ZitazioaThornbury, William David. Principles Geomorphology. Wiley, 1969.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.