Dyfyniad APA

Hatfield, J. (1994). Soil biology: Effects on soil quality. Lewis Publishers.

Dyfyniad Arddull Chicago

Hatfield, J.L. Soil Biology: Effects on Soil Quality. Boca Raton: Lewis Publishers, 1994.

Dyfyniad MLA

Hatfield, J.L. Soil Biology: Effects on Soil Quality. Lewis Publishers, 1994.

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