1. Bramwell, C.: Formal development methods for interactive systems: Combining interactors and design rationale (1996)
2. de Haan, G.: ETAG: A Formal Model of Competence Knowledge for User-Interface Design. PhD thesis, Vrije Universiteit, Amsterdam (2000)
3. Dierstein, R.: Sicherheit in der Informationstechnik: Der Begriff IT-Sicherheit. Informatik Spektrum 27(4) (August 2004)
4. Dix, A., Abowd, G.: Modelling status and event behaviour of interactive systems. Software Engineering Journal 11(6), 334–346 (1996)
5. Dix, A., Runciman, C.: Abstract models of interactive systems. In: Johnson, P., Cook, S. (eds.) HCI 1985: People and Computers I: Designing the Interface, pp. 13–22. Cambridge University Press, Cambridge (1985)