Dyfyniad APA

Gilluly, J. (1968). Principles of geology (3rd ed.). W H Freeman.

Dyfyniad Arddull Chicago

Gilluly, James. Principles of Geology. 3rd ed. Sanfrancisco: W H Freeman, 1968.

Dyfyniad MLA

Gilluly, James. Principles of Geology. 3rd ed. W H Freeman, 1968.

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