Dyfyniad APA

(2017). Earth: An introduction to physical geology. Pearson Education.

Dyfyniad Arddull Chicago

Earth: An Introduction to Physical Geology. Pearson Education, 2017.

Dyfyniad MLA

Earth: An Introduction to Physical Geology. Pearson Education, 2017.

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