X. Chai, B. Vuong, A. Doan, and J. Naughton. Proceedings of the 35th SIGMOD international conference on Management of data, page 87--100. New York, NY, USA, ACM, (2009)
S. Javanmardi, D. McDonald, and C. Lopes. Proceedings of the 7th International Symposium on Wikis and Open Collaboration, page 82--90. New York, NY, USA, ACM, (2011)
E. Michlmayr, and S. Cayzer. Proceedings of the Workshop on Tagging and Metadata for Social Information Organization, 16th International World Wide Web Conference, (2007)
Y. Jin, Y. Matsuo, and M. Ishizuka. Proceedings of the European Semantic Web Conference, ESWC2007, volume 4519 of Lecture Notes in Computer Science, Springer-Verlag, (July 2007)