Dyfyniad APA

Perrin, W. F., Würsig, B. G., & Thewissen, J. G. M. (2009). Encyclopedia of marine mammals (2nd ed.). Elsevier/Academic Press.

Dyfyniad Arddull Chicago

Perrin, W. F., Bernd G. Würsig, and J. G. M. Thewissen. Encyclopedia of Marine Mammals. 2nd ed. Amsterdam ; Boston, Mass.: Elsevier/Academic Press, 2009.

Dyfyniad MLA

Perrin, W. F., et al. Encyclopedia of Marine Mammals. 2nd ed. Elsevier/Academic Press, 2009.

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