user- (2005)
- Behaviour and Information Technology 24(1):51--66 (2005)
- Proceedings of the 3rd conference on Designing interactive systems: processes, practices, methods, and techniques, page 193--202. New York, NY, USA, ACM, (2000)
- The International Review of Research in Open and Distance Learning (2007)
- Proceedings of the First International Conference on Practical Applications of Intelligent Agents and Multi-Agents Technology PAAM96, page 837-842. London, UK, (1996)
- CHI '90: Proceedings of the SIGCHI conference on Human factors in computing systems, page 249-256. New York, NY, ACM Press, (1990)
- Proceedings of the IFIP 8th International Conference on Human-Computer Interaction INTERACT-03 (2003)
- SAICSIT National Research and Development Seminar, Pretoria, (1995)
- Prentice Hall, 3rd edition, (2004)
- page 25-62. John Wiley & Sons, Inc., New York, NY, USA, (1994)
