Dyfyniad APA

Birdsall, S. S., & Florin, J. (1992). Outline of American Geography. New York: John Wiley & Sons.

Dyfyniad Arddull Chicago

Birdsall, Stephen S., và John Florin. Outline of American Geography. New York: John Wiley & Sons, 1992.

Dyfyniad MLA

Birdsall, Stephen S., và John Florin. Outline of American Geography. New York: John Wiley & Sons, 1992.

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