Dyfyniad APA

Osborn, F. (1953). The limits of the earth. Little, Brown.

Dyfyniad Arddull Chicago

Osborn, Fairfield. The Limits of the Earth. Boston: Little, Brown, 1953.

Dyfyniad MLA

Osborn, Fairfield. The Limits of the Earth. Little, Brown, 1953.

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