Howard Bowman Rodolfo Gómez Li Su A Tool for the Syntactic Detection of Zeno-timelocks in Timed Automata. 25-47 2005 139 Electr. Notes Theor. Comput. Sci. 1 http://dx.doi.org/10.1016/j.entcs.2005.09.006 db/journals/entcs/entcs139.html#BowmanGS05