Dyfyniad APA

Journal of the Pennsylvania Academy of Science. Penn State University Press.

Dyfyniad Arddull Chicago

Journal of the Pennsylvania Academy of Science. Penn State University Press.

Dyfyniad MLA

Journal of the Pennsylvania Academy of Science. Penn State University Press.

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