1. Burnett, G.E.: “Turn right at the traffic lights” The requirement for landmarks in vehicle navigation systems. The Journal of Navigation 53(3), 499–510 (2000)
2. Byers, J.C., Bittner Jr, A.C., Hill, S.G.: Traditional and Raw Task Load Index (TLX) Correlations: Are Paired Comparisons Necessary? In: Mital, A. (ed.) Advances in Industrial Ergonomics and Safety I, pp. 481–485. Taylor & Francis, Abington (1989)
3. Eisma, R., Dickinson, A., Goodman, J., Syme, A., Tiwari, L., Newell, A.F.: Early User Involvement in the Development of Information Technology-Related Products for Older People. To appear in Design Principles to Support Older Adults, Special Issue of Universal Access in the Information Society 3(2) (2004) (to appear)
4. Garmin, http://www.garmin.com
5. Goodman, J., Dickinson, A., Syme, A.: Gathering Requirements for Mobile Devices using Focus Groups with Older People. To appear in Designing a More Inclusive World. In: Proceedings of the 2nd Cambridge Workshop on Universal Access and Assistive Technology (CWUAAT), Springer, Heidelberg (2004)