S. Gutierrez-Santos, M. Mavrikis, and G. Magoulas. Proceedings of the Tenth International Conference on Intelligent Tutoring Systems: Bridges to Learning, volume 6094 of Lecture Notes in Computer Science, page 105--114. Berlin, Heidelberg, Springer Berlin / Heidelberg, (2010)
V. Devedzic, J. Good, A. Harrer, R. Luckin, D. Pearce, S. Retalis, and J. Robertson. Artificial Intelligence in Education - Building Technology Rich Learning Contexts that Work, volume 158 of Frontiers in Artificial Intelligence and Applications, page 715. Amsterdam, IOS Press, (2007)
E. Gouli, A. Gogoulou, and M. Grigoriadou. Proceedings of the ED-MEDIA 2006, World Conference on Educational Multimedia, Hypermedia & Telecommunications, (2006)