Crowdsourcing, citizen science or volunteered geographic information? The current state of crowdsourced geographic information.

See, L.; Mooney, P.; Foody, G.; Bastin, L.; Comber, A.; Estima, J.; Fritz, S.; Kerle, N.; Jiang, B.; Laakso, M.; Liu, H.-Y.; Milcinski, G.; Niksic, M.; Painho, M.; Podör, A.; Olteanu-Raimond, A.-M.; Rutzinger, M.