Dyfyniad APA

Covington, G. (2010). International encyclopedia of sustainable development. Apple academic.

Dyfyniad Arddull Chicago

Covington, Gareth. International Encyclopedia of Sustainable Development. Oakville: Apple academic, 2010.

Dyfyniad MLA

Covington, Gareth. International Encyclopedia of Sustainable Development. Apple academic, 2010.

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