Dyfyniad APA

Bonnet, R. L., & Keen, G. D. (1990). Environmental science: 49 science fair projects. TAB Books.

Dyfyniad Arddull Chicago

Bonnet, Robert L., and G. Daniel Keen. Environmental Science: 49 Science Fair Projects. Blue Ridge Summit, PA: TAB Books, 1990.

Dyfyniad MLA

Bonnet, Robert L., and G. Daniel Keen. Environmental Science: 49 Science Fair Projects. TAB Books, 1990.

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