Marcin Jurdzinski Marta Z. Kwiatkowska Gethin Norman Ashutosh Trivedi Concavely-Priced Probabilistic Timed Automata. 415-430 2009 CONCUR http://dx.doi.org/10.1007/978-3-642-04081-8_28 conf/concur/2009 db/conf/concur/concur2009.html#JurdzinskiKNT09