APA aipamena

Estes, J. S. ;. J. (1990). Geographic Information Systems An Introduction. Prentice Hall.

Chicago Style aipamena

Estes, Jeffrey Star ; John. Geographic Information Systems An Introduction. Prentice Hall, 1990.

MLA aipamena

Estes, Jeffrey Star ; John. Geographic Information Systems An Introduction. Prentice Hall, 1990.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.