Dyfyniad APA

Heywood, I., Cornelius, S., & Carver, S. (2003). An Introduction to Geographical Information Systems (2nd ed.). Pearson Education (Singapore) Pte. Ltd.

Dyfyniad Arddull Chicago

Heywood, Ian, Sarah Cornelius, and Steve Carver. An Introduction to Geographical Information Systems. 2nd ed. Delhi: Pearson Education (Singapore) Pte. Ltd, 2003.

Dyfyniad MLA

Heywood, Ian, et al. An Introduction to Geographical Information Systems. 2nd ed. Pearson Education (Singapore) Pte. Ltd, 2003.

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