Database and Expert Systems Applications 15th International Conference, DEXA 2004, Zaragoza, Spain, August 30-September 3, 2004, Proceedings - Galindo, Fernando; Galindo, Fernando; Takizawa, Makoto; Takizawa, Makoto; Traunmüller, Roland; Traunmüller, Roland (Springer Berlin Heidelberg : Imprint: Springer, 2004)