Henzinger TA, Kopke P, Wong Toi H. 1995. The expressive power of clocks. 22nd International Colloquium on Automata, Languages and Programming . ICALP: Automata, Languages and Programming, LNCS, vol. 944, 417–428.
LibreCat: https://research-explorer.ista.ac.at/record/4500
DOI: 10.1007/3-540-60084-1_93

Henzinger TA. 1995. Hybrid automata with finite bisimulations. 22nd International Colloquium on Automata, Languages and Programming . ICALP: Automata, Languages and Programming, LNCS, vol. 944, 324–335.
LibreCat: https://research-explorer.ista.ac.at/record/4518
DOI: 10.1007/3-540-60084-1_85