Dyfyniad APA

Brady, N. C., & Weil, R. R. (2002). nature and properties of soils (13th ed.). Pearson Education.

Dyfyniad Arddull Chicago

Brady, Nyle C., and Ray R. Weil. Nature and Properties of Soils. 13th ed. Delhi: Pearson Education, 2002.

Dyfyniad MLA

Brady, Nyle C., and Ray R. Weil. Nature and Properties of Soils. 13th ed. Pearson Education, 2002.

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