Peter Widmayer, Francisco Triguero Ruiz, Rafael Morales Bueno, Matthew Hennessy, Stephan J. Eidenbenz, Ricardo Conejo: Automata, Languages and Programming, 29th International Colloquium, ICALP 2002, Malaga, Spain, July 8-13, 2002, Proceedings. Lecture Notes in Computer Science 2380, Springer 2002, ISBN 3-540-43864-5