DeMers, M. N. (2009). Fundamentals of geographic information systems (Forth edition.). Wiley.
Lua i Stíl Chicago (17ú heag.)DeMers, Michael N. Fundamentals of Geographic Information Systems. Forth edition. Hoboken, NJ ; India: Wiley, 2009.
Lua MLA (8ú heag.)DeMers, Michael N. Fundamentals of Geographic Information Systems. Forth edition. Wiley, 2009.
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