Dyfyniad APA

Walther, J. (2014). Earth's natural resources. Jones & Bartlett Learning.

Dyfyniad Arddull Chicago

Walther, John. Earth's Natural Resources. Burlington, MA: Jones & Bartlett Learning, 2014.

Dyfyniad MLA

Walther, John. Earth's Natural Resources. Jones & Bartlett Learning, 2014.

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