Allen, D. W. (2011). GIS tutorial 3: Advanced workbook. ESRI Press.
Chicago Style aipamenaAllen, David W. GIS Tutorial 3: Advanced Workbook. Redlands, Calif: ESRI Press, 2011.
MLA aipamenaAllen, David W. GIS Tutorial 3: Advanced Workbook. ESRI Press, 2011.
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