Dyfyniad APA
Tarbuck, E. J., & Lutgens, F. K. (1997). Earth science (8th.ed.). Prentice Hall.
Dyfyniad Arddull Chicago
Tarbuck, Edward J., and Frederick K. Lutgens. Earth Science. 8th.ed. New Jersey: Prentice Hall, 1997.
Dyfyniad MLA
Tarbuck, Edward J., and Frederick K. Lutgens. Earth Science. 8th.ed. Prentice Hall, 1997.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.