Wilpen L. Gorr, & Wilpen L. Gorr; Kristen S. Kurland. (2007). Learning and using geographic information systems: ArcGIS edition. Boston, Mass: Thomson Course Technology.
Čikaški stil citiranjaWilpen L. Gorr, i Wilpen L. Gorr; Kristen S. Kurland. Learning and Using Geographic Information Systems: ArcGIS Edition. Boston, Mass: Thomson Course Technology, 2007.
MLA način citiranjaWilpen L. Gorr, i Wilpen L. Gorr; Kristen S. Kurland. Learning and Using Geographic Information Systems: ArcGIS Edition. Boston, Mass: Thomson Course Technology, 2007.
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