Dyfyniad APA

(2004). Fifty great thinkers on the environment. Routledge.

Dyfyniad Arddull Chicago

Fifty Great Thinkers on the Environment. London: Routledge, 2004.

Dyfyniad MLA

Fifty Great Thinkers on the Environment. Routledge, 2004.

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