Dyfyniad APA

Clarke, K. C. (2003). Getting started with geographic information systems (4th ed.). Pearson Education.

Dyfyniad Arddull Chicago

Clarke, Keith C. Getting Started with Geographic Information Systems. 4th ed. Upper Saddle River, N.J: Pearson Education, 2003.

Dyfyniad MLA

Clarke, Keith C. Getting Started with Geographic Information Systems. 4th ed. Pearson Education, 2003.

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