Dyfyniad APA

Berck, P., & Helfand, G. (2011). Economics of the environment: Peter Berck and Gloria Helfand. Addison - Wesley.

Dyfyniad Arddull Chicago

Berck, Peter, and Gloria Helfand. Economics of the Environment: Peter Berck and Gloria Helfand. Boston: Addison - Wesley, 2011.

Dyfyniad MLA

Berck, Peter, and Gloria Helfand. Economics of the Environment: Peter Berck and Gloria Helfand. Addison - Wesley, 2011.

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