Wilpen L. Gorr, & Wilpen L. Gorr; Kristen S. Kurland. (2007). Learning and using geographic information systems: ArcGIS edition. Boston, Mass: Thomson Course Technology.
استشهاد بنمط شيكاغوWilpen L. Gorr, و Wilpen L. Gorr; Kristen S. Kurland. Learning and Using Geographic Information Systems: ArcGIS Edition. Boston, Mass: Thomson Course Technology, 2007.
MLA استشهادWilpen L. Gorr, و Wilpen L. Gorr; Kristen S. Kurland. Learning and Using Geographic Information Systems: ArcGIS Edition. Boston, Mass: Thomson Course Technology, 2007.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.