1. Ruël, G.C., Bastiaans, N., Nauta, A.: Free-riding and team performance in project education. Technical report, Research Report 03A42, University of Groningen, Research Institute SOM (Systems, Organisations and Management) (2003)
2. Johnson, D.W., Johnson, R.T.: Learning Together and Alone: Cooperative, Competitive, and Individualistic Learning. Allyn & Bacon, Boston (1998)
3. McConnell, D.: Implementing Computer Supported Cooperative Learning. Stylus Publishing, LLC (2000)
4. Weisband, S.: Overcoming social awareness in computer-supported groups. Computer Supported Cooperative Work (CSCW) 2(4), 285–297 (1994)
5. Weisband, S.P., Schneider, S.K., Connolly, T.: Computer-mediated communication and social information: Status salience and status differences. The Academy of Management Journal 38(4), 1124–1151 (1995)