Dyfyniad APA

Kummel, B. (1961). History of the earth: :introduction to histrocal geology. Eurasia publishing.

Dyfyniad Arddull Chicago

Kummel, Bernhard. History of the Earth: :introduction to Histrocal Geology. New delhi: Eurasia publishing, 1961.

Dyfyniad MLA

Kummel, Bernhard. History of the Earth: :introduction to Histrocal Geology. Eurasia publishing, 1961.

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