Dyfyniad APA

Peter W Birkeland. (1984). Soils and geomorphology. New York: Oxford University.

Dyfyniad Arddull Chicago

Peter W Birkeland. Soils and Geomorphology. New York: Oxford University, 1984.

Dyfyniad MLA

Peter W Birkeland. Soils and Geomorphology. New York: Oxford University, 1984.

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