Dyfyniad APA

Chrisman, N. R. (1997). Exploring geographic information systems. New York: John Wiley and Sons.

Dyfyniad Arddull Chicago

Chrisman, Nicholas R. Exploring Geographic Information Systems. New York: John Wiley and Sons, 1997.

Dyfyniad MLA

Chrisman, Nicholas R. Exploring Geographic Information Systems. New York: John Wiley and Sons, 1997.

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