Dyfyniad APA

C.Plummer Charles, & H.Carlson Diane. (2003). Physical Geology. American: McGraw -Hill.

Dyfyniad Arddull Chicago

C.Plummer Charles, và H.Carlson Diane. Physical Geology. American: McGraw -Hill, 2003.

Dyfyniad MLA

C.Plummer Charles, và H.Carlson Diane. Physical Geology. American: McGraw -Hill, 2003.

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