Dyfyniad APA

DeMERS, M. N. (1997). Fundamentals of geographic information systems. John Wiley and Sons.

Dyfyniad Arddull Chicago

DeMERS, Michael N. Fundamentals of Geographic Information Systems. New York: John Wiley and Sons, 1997.

Dyfyniad MLA

DeMERS, Michael N. Fundamentals of Geographic Information Systems. John Wiley and Sons, 1997.

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