Intelligent Tutoring Systems 7th International Conference, ITS 2004, Maceió, Alagoas, Brazil, August 30 - September 3, 2004, Proceedings - Lester, James C.; Lester, James C.; Vicari, Rosa Maria; Vicari, Rosa Maria; Paraguacu, Fábio; Paraguacu, Fábio (Springer Berlin Heidelberg : Imprint: Springer, 2004)