1. Cockton, G. & Lavery, D. (1999). A framework for usability problem extraction. In M. A. Sasse & C. Johnson (Eds.), Seventh IFIP Conference on Human-Computer Interaction Incorporating HCI '99 (pp. 344-352). Amsterdam: IOS Press.
2. Cockton, G. & Woolrych, A. (2001). Understanding inspection methods: Lessons from an assessment of heuristic evaluation. In A. Blandford, J. Vanderdonckt, & P. D. Gray (Eds.), People and computers: Vol. 15. Joint proceedings of HCI 2001 and IHM 2001 (pp. 171-192). Berlin: Springer-Verlag.
3. Erickson, T. D. (1990). Working with interface metaphors. In B. Laurel (Ed.), The art of human computer interface design (pp. 65-73). Reading, MA: Addison-Wesley.
4. Fleiss, J. L. (1981). Statistical methods for rates and proportions. New York: Wiley.
5. Frokjaer, E. & Hornbaek, K. (2002). Metaphors of human thinking in HCI: Habit, stream of thought, awareness, utterance, and knowing. In R. Kuchinsky, L. Johnson, & F. Vetere (Eds.), Proceedings of HF2002/OzCHI 2002 (CD-Rom). Australia: CHISIG.