Dyfyniad APA

(1987). Protecting the nations ground water from contamination. Scientific Publishers.

Dyfyniad Arddull Chicago

Protecting the Nations Ground Water from Contamination. Jodhpur: Scientific Publishers, 1987.

Dyfyniad MLA

Protecting the Nations Ground Water from Contamination. Scientific Publishers, 1987.

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