Dyfyniad APA

Gartrell, J. E., Crowder, J., & Callister, J. C. (1992). Earth: The water planet (Rev. ed.). National Science Teachers Association.

Dyfyniad Arddull Chicago

Gartrell, Jack E., Jane Crowder, and Jeffrey C. Callister. Earth: The Water Planet. Rev. ed. Arlington, Va.: National Science Teachers Association, 1992.

Dyfyniad MLA

Gartrell, Jack E., et al. Earth: The Water Planet. Rev. ed. National Science Teachers Association, 1992.

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