2003.
@proceedings{ICDT-2003-ed, title = "Proc. of the 9th Int. Conf. on Database Theory (ICDT 2003)", year = "2003", editor = "Diego Calvanese and Maurizio Lenzerini and Rajeev Motwani", volume = "2572", publisher = "Springer", series = "Lecture Notes in Computer Science", doi = "10.1007/3-540-36285-1", }url