- Artificial Intelligence 42(1):7-49 (1990)
- International Encyclopedia of the Social and Behavioral Sciences, 2.2, Pergamon, Oxford, (2004)
- (2000)
- Wiley, New York, 2 edition, (2000)
- Human Computer Interaction Research in Web Design and Evaluation, Idea Group, Hershey, (2006)
- page 304-309. (2006)
- (2006)
- Cognitive Science 26(1):85-112 (2002)
- (2006)
- Cognitive Science 27(4):591-635 (2003)
- Psychological Review 111(4):1036-1060 (2004)


user