Dyfyniad APA

Lehmann. Ringer. University of Pittsburgh Press.

Dyfyniad Arddull Chicago

Lehmann. Ringer. University of Pittsburgh Press.

Dyfyniad MLA

Lehmann. Ringer. University of Pittsburgh Press.

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