- Mensch \& Computer 2009, Berlin, (2009)
- American psychologist (1995)
- PADI Research Group, (2004)
- Knowledge Spaces: Theories, Empirical Research, Applications, Lawrence Erlbaum Associates, Mahwah, NJ, (1999)
- EARLI (2006)
- Journal of Mathematical Psychology 45(3):480 - 496 (2001)
- Ergonomics 41(11):1618--1641 (1998)
- Discourse processes (1998)
- Cognitive task analysis (2000)
- Journal of Interactive Learning Research 18(2):231--250 (April 2007)
- Proceedings of the international Conference on Computers in Education ICCE 2007, (2007)
- Gesellschaftliche und indiviuelle Entwicklung in Japan und Deutschland, Universitäts-Verlag Konstanz, (1996)
- CAS (2008)
- HCI and Usability for Medicine and Health Care. Proceedings of the Third Symposium of the Workgroup Human-Computer Interaction and Usability Engineering of the Austrian Computer Society, USAB 2007 Graz, Austria, November, 22, 2007, volume 4799 of Lecture Notes in Computer Science, page 165--170. Berlin, Springer, (2007)
- Annual review of psychology 54(1):547--577 (2003)
- Proceed of 8. International Conference on Computer Supported Collaborative Learning CSCL2009 (June 2009)
- Behavior Research Methods Instruments and Computers (1996)
- GoTAL, page 28-39. (2008)
- Scandinavian Journal of Psychology 39(1):39-45 (1998)


user