Dyfyniad APA

Westerman. Working on Earth. University of Nevada Press.

Dyfyniad Arddull Chicago

Westerman. Working on Earth. University of Nevada Press.

Dyfyniad MLA

Westerman. Working on Earth. University of Nevada Press.

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