1. Baghaei, N., Mitrovic, A., Irwin, W.: A Constraint-Based Tutor for Learning Object Oriented Analysis and Design using UML. In: Proc. ICCE 2005, pp.11–18 (2005)
2. Baghaei, N., Mitrovic, A.: A Constraint-based Collaborative Environment for Learning UML Class Diagrams. In: Proc. ITS 2006, pp.176–186 (2006)
3. Baghaei, N., Mitrovic, A., Irwin, W.: Problem-Solving Support in a Constraint-based Tutor for UML Class Diagrams, Technology, Instruction, Cognition and Learning Journal, 4(2), 2006 (in print)
4. Brusilovsky, P., Peylo, C.: Adaptive and Intelligent Web-based Educational Systems. Artificial Intelligence in Education 13, 159–172 (2003)
5. Constantino-Gonzalez, M.A., Suthers, D., de los Santos, E.J.: Coaching web- based collaborative learning based on problem solution differences and participation. Int. J. Artificial Intelligence in Education 13(2-4), 263–299 (2003)