APA (7th ed.) Citation

Christopherson, R. W., & Birkeland, G. H. (2015). Geosystems: An introduction to physical geography (Ninth edition.). Pearson.

Chicago Style (17th ed.) Citation

Christopherson, Robert W., and Ginger H. Birkeland. Geosystems: An Introduction to Physical Geography. Ninth edition. Boston: Pearson, 2015.

MLA (9th ed.) Citation

Christopherson, Robert W., and Ginger H. Birkeland. Geosystems: An Introduction to Physical Geography. Ninth edition. Pearson, 2015.