APA (7th ed.) Citation
Wallen, R. N. (1992). Introduction to physical geography. WM C. Brown.
Chicago Style (17th ed.) Citation
Wallen, Robert N. Introduction to Physical Geography. Boulevard: WM C. Brown, 1992.
MLA (9th ed.) Citation
Wallen, Robert N. Introduction to Physical Geography. WM C. Brown, 1992.
Warning: These citations may not always be 100% accurate.