Dyfyniad APA

Charles A Black. (1993). Soil fertility evaluation and control. Boca Raton: Lewis Publishers.

Dyfyniad Arddull Chicago

Charles A Black. Soil Fertility Evaluation and Control. Boca Raton: Lewis Publishers, 1993.

Dyfyniad MLA

Charles A Black. Soil Fertility Evaluation and Control. Boca Raton: Lewis Publishers, 1993.

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