Dyfyniad APA

(1991). Modeling plant and soil systems. Wisconsin, USA: American Society of Agronomy, Inc.

Dyfyniad Arddull Chicago

Modeling Plant and Soil Systems. Wisconsin, USA: American Society of Agronomy, Inc, 1991.

Dyfyniad MLA

Modeling Plant and Soil Systems. Wisconsin, USA: American Society of Agronomy, Inc, 1991.

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