Automata, Languages and Programming 24th International Colloquium, ICALP'97, Bologna, Italy, July 7 - 11, 1997, Proceedings - Degano, Pierpaolo; Degano, Pierpaolo; Gorrieri, Roberto; Gorrieri, Roberto; Marchetti-Spaccamela, Alberto; Marchetti-Spaccamela, Alberto (Springer Berlin Heidelberg : Imprint: Springer, 1997)