Dyfyniad APA

Pearl, R. M. (1955). How to know the minerals and rocks. New York: McGraw-Hill.

Dyfyniad Arddull Chicago

Pearl, Richard M. How to Know the Minerals and Rocks. New York: McGraw-Hill, 1955.

Dyfyniad MLA

Pearl, Richard M. How to Know the Minerals and Rocks. New York: McGraw-Hill, 1955.

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