1. Barros, B. & Verdejo M.F (2000). “Analysing students interaction process for improving collaboration. The DEGREE approach”, International Journal of Artificial Intelligence in Education.
2. Barros, B., Mizoguchi, R. & Verdejo M.F (2001). A Platform for Collaboration Analysis in CSCL: An ontological approach, Proc. AIED’2001, May 19–23, 2001.
3. Brown, J. S. (1983) “Process versus product: a perspective on tools for communal and informal electronic learning”, Report from the Learning: Education in the Electronic Age.
4. Dillenbourg, P., Baker, H.P.M., Blaye, A. & O'Malley (1995) “The evolution of research on collaborative Learning” http://tecfa.unige.ch/tecfa/researchUlhm/ESF-Chap5.ps
5. Duffy, T.M., Lowyck, J. & Jonassen, D. (1992) Designing Environments for Constructive Learning, Sprinver-Verlag.