1. Open Data Institute: Open Data Barometer—2013 Global Reporthttp://www.opendataresearch.org/dl/odb2013/Open-Data-Barometer-2013-Global-Report.pdf
2. FixMyStreethttp://www.fixmystreet.com/
3. FixMyTransporthttp://www.fixmytransport.com/
4. The rise of crowdsourcing;Howe;Wired Mag.,2006
5. Wikipedia, the Free Encyclopaediahttp://www.wikipedia.org