1. Bloom, B. (1956). Taxonomy of Educational Objectives. New York: David McKay Company.
2. Conklin, J. (1987). Hypertext: An introduction and survey. IEEE Computer, 20(9), 17–41.
3. Gay, G., & Raffensperger, E. (1989). Considerations and strategies in the design of interactive multimedia programs. Academic Computing, 4(1), 24–25, 57–58.
4. Hammond, N., & Allinson, L. (1989). Extending hypertext for learning: An investigation of access and guidance tools. In: A. Sutcliffe & L. Macaulay (Eds). People and Computers V, 293–304. Cambridge: Cambridge University Press.
5. Hammond, N. (1990). Teaching with hypermedia: Problems and prospects. In: H. Brown (Ed.). Hypermedia, Hypertext and Object-Oriented Databases. Chapman & Hall.