APA (7th ed.) Zitazioa
Daniel Sui, S. E. Crowdsourcing Geographic Knowledge: Volunteered Geographic Information (VGI) in Theory and Practice. Springer.
Chicago Style (17th ed.) Zitazioa
Daniel Sui, Sarah Elwood. Crowdsourcing Geographic Knowledge: Volunteered Geographic Information (VGI) in Theory and Practice. Dordrecht, Holanda: Springer.
MLA (9th ed.) Zitazioa
Daniel Sui, Sarah Elwood. Crowdsourcing Geographic Knowledge: Volunteered Geographic Information (VGI) in Theory and Practice. Springer.
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