@book {2, title = {Methods and Applications of Artificial Intelligence Third Helenic Conference on AI, SETN 2004}, series = {Lecture Notes in Computer Science}, volume = { 3025}, year = {2004}, publisher = {Springer Verlag}, organization = {Springer Verlag}, isbn = {978-3-540-21937-8}, url = {http://www.springer.com/computer/artificial/book/978-3-540-21937-8}, author = {G. Vouros and T. Panayiotopoulos} }