Dyfyniad APA

(1991). Environmental economics. New Delhi: Mittal Publications.

Dyfyniad Arddull Chicago

Environmental Economics. New Delhi: Mittal Publications, 1991.

Dyfyniad MLA

Environmental Economics. New Delhi: Mittal Publications, 1991.

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