Dyfyniad APA

Gregory, K. J., & Walling, D. E. (1979). Man and environmental processes: A physical geography perspective. Dawson [etc.].

Dyfyniad Arddull Chicago

Gregory, K. J., and D. E. Walling. Man and Environmental Processes: A Physical Geography Perspective. Folkestone: Dawson [etc.], 1979.

Dyfyniad MLA

Gregory, K. J., and D. E. Walling. Man and Environmental Processes: A Physical Geography Perspective. Dawson [etc.], 1979.

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