Dyfyniad APA

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

Dyfyniad Arddull Chicago

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

Dyfyniad MLA

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

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.