De By, R. A. (2001). Principles of geographic information systems: An introductory textbook (2nd ed.). International Institute Aerospace Survey and Earth Sciences (ITC).
Chicago Style (17. basım) AtıfDe By, Rolf A. Principles of Geographic Information Systems: An Introductory Textbook. 2nd ed. Enschede, The Netherlands: International Institute Aerospace Survey and Earth Sciences (ITC), 2001.
MLA (9th ed.) AtıfDe By, Rolf A. Principles of Geographic Information Systems: An Introductory Textbook. 2nd ed. International Institute Aerospace Survey and Earth Sciences (ITC), 2001.
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