Dyfyniad APA

Cowen, R. (1990). History of life. Blackwell Scientific Publications.

Dyfyniad Arddull Chicago

Cowen, Richard. History of Life. Boston: Blackwell Scientific Publications, 1990.

Dyfyniad MLA

Cowen, Richard. History of Life. Blackwell Scientific Publications, 1990.

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