author- Taylor & Francis, (2009)
- ICLS 1, page 85-92. International Society of the Learning Sciences, (2008)
- ICLS 3, page 266-273. International Society of the Learning Sciences, (2008)
- Cognitive Technology, volume 2117 of Lecture Notes in Computer Science, page 267-281. Springer, (2001)
- International Journal of Computers for Mathematical Learning 9(3):309--326 (2004)
- proceedings of the 1st CSCL SIG Symposium, Lausanne, Switzerland, (2004)
- the International Journal for Technology in Mathematics Education 13(2):65-78 (2006)
- the 7th International Conference on Technology in Mathematics Teaching, Bristol, (2005)
- Fourth Congress of the European Society for Research in Mathematics Education CERME-4, Sant Feliu de Guíxols, Spain, (2005)
- International Journal of Continuing Engineering Education and Life-Long Learning IJCEELL 18(2):214-233 (2008)
- Micromath 20(2):17-23 (2004)
- University of Illinois Press, Urbana, (1989)
- J. Comp. Assisted Learning 22(2):114-136 (2006)
- J. Comp. Assisted Learning 21(2):143-158 (2005)
- Lecture Notes in Computer Science (2006)
- (2004)
- International Journal of Continuing Engineering Education and Life Long Learning 12(5):521-540 (2002)
- Cognitive Technology, volume 2117 of Lecture Notes in Computer Science, page 267-281. Springer, (2001)
- AIED, volume 200 of Frontiers in Artificial Intelligence and Applications, page 804. IOS Press, (2009)
- (2005)
