1. Stahl, G., Koschmann, T., Suthers, D.: Computer-supported collaboratives learning: an historical perspective. In: Sawyer, R.K. (ed.) Cambridge Handbook of the Learning Sciences, pp. 409–426. Cambridge University Press, Cambridge (2006)
2. Attwell, G., Baumgartl, B.: Creating Learning Spaces: Training and Professional Development for Trainers. Navreme, Vienna (2008)
3. Eraut, M.: Non-formal learning and tacit knowledge in professional work. Br. J. Educ. Psychol. 70(1), 113–136 (2000)
4. Lecture Notes in Computer Science;J Kooken,2007
5. Marsick, V.J., Volpe, M.: The nature and need for informal learning. Adv. Developing Hum. Resour. 1(3), 1–9 (1999)