Dyfyniad APA

Simpson. River City and Valley Life. University of Pittsburgh Press.

Dyfyniad Arddull Chicago

Simpson. River City and Valley Life. University of Pittsburgh Press.

Dyfyniad MLA

Simpson. River City and Valley Life. University of Pittsburgh Press.

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