1. Ahlfeldt, S., Mehtab, S., & Sellnow, T. (2005, February). Measurement and analysis of student engagement in university classes where varying levels of PBL methods of instruction are in use. Higher Education Research & Development, 24(1), 5–20.
2. Annetta, L. A., & Holmes, S. (2006). Creating presence and community in a sycnhronous virtual learning environment using avatars. International Journal of Instructional Technology and Distance Learning, 3(8).
3. Bainbridge, W. (2007). The scientific research potential of virtual worlds. Science, 317, 472.
4. Brewster, C., & Fager, J. (2000) Increasing student engagement and motivation: From time on task to homework [online]. Northwest Regional Educational Laboratory. Retrieved from http://www.nwrel.org/request/oct00/textonly.html
5. Brown, J. S., Collins, A., & Duguid, S. (1989). Situated cognition and the culture of learning. Educational Researcher, 18(1), 32–42.