1. Collaborative virtual environments: a conference report;Snowdon;SIGGROUP Bulletin,1998
2. What do you mean by collaborative learning?;Dillenbourg,1999
3. Towards a cognitive approach to human-machine cooperation in dynamic situations;Hoc;IJHCS,2001
4. Grounding in communication;Clark,1991
5. Touch, gesture and marking;Buxton,1995