Dyfyniad APA

 Engelman, R. (2008).  More: Population, nature, and what women want.  Island Press.

Dyfyniad Arddull Chicago

 Engelman, Robert.  More: Population, Nature, and What Women Want.  Island Press, 2008.

Dyfyniad MLA

 Engelman, Robert.  More: Population, Nature, and What Women Want.  Island Press, 2008.

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