Dyfyniad APA

Gardiner, D. T., & Miller, R. W. (2008). Soils in our environment (11th ed.). Pearson/Prentice Hall.

Dyfyniad Arddull Chicago

Gardiner, Duane T., and Raymond W. Miller. Soils in Our Environment. 11th ed. Upper Saddle River, N.J: Pearson/Prentice Hall, 2008.

Dyfyniad MLA

Gardiner, Duane T., and Raymond W. Miller. Soils in Our Environment. 11th ed. Pearson/Prentice Hall, 2008.

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