C. Robardet, and F. Feschet. IDEAL '00: Proceedings of the Second International Conference on Intelligent Data Engineering and Automated Learning, Data Mining, Financial Engineering, and Intelligent Agents, page 565--570. London, UK, Springer-Verlag, (2000)
O. Rostanin, and R. Schirru. Proceedings of the Joint International Workshop on Professional Learning, Competence Development and Knowledge Management - LOKMOL and L3NCD held in conjunction with the 1st European Conference on Technology Enhanced Learning, page 53-58. (October 2006)