Dyfyniad APA

The Geological Society of America. Geological Society of America Bulletin. The Geological Society of America.

Dyfyniad Arddull Chicago

The Geological Society of America. Geological Society of America Bulletin. The Geological Society of America.

Dyfyniad MLA

The Geological Society of America. Geological Society of America Bulletin. The Geological Society of America.

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