Automata, languages and programming : 36th international Colloquium, ICALP 2009, Rhodes, Greece, July 5-12, 2009 : proceedings - Albers, Susanne B., 1965-; Marchetti-Spaccamela, Alberto; Matias, Yossi; Nikoletseas, Sotiris; Thomas, Wolfgang (Lecture notes in computer science, Advanced research in computing and software science, 2009)