Jianhua Zhao Xuandong Li Tao Zheng Guoliang Zheng Remove Irrelevant Atomic Formulas for Timed Automaton Model Checking. 41-51 2006 21 J. Comput. Sci. Technol. 1 http://dx.doi.org/10.1007/s11390-006-0041-9 db/journals/jcst/jcst21.html#ZhaoLZZ06