U. Riss, U. Cress, J. Kimmerle, and S. Martin. Proceedings of KMAC2006, The Third Knowledge Management Aston Conference, Operational Research Society, Birmingham, (2006)
J. Goecks, and E. Mynatt. CSCW '04: Proceedings of the 2004 ACM conference on Computer supported cooperative work, page 328--331. New York, NY, USA, ACM Press, (2004)
J. Mori, T. Sugiyama, and Y. Matsuo. GROUP '05: Proceedings of the 2005 international ACM SIGGROUP conference on Supporting group work, page 81--84. New York, NY, USA, ACM Press, (2005)