In: International Journal of Systems Science, Vol. 24, No. 3, pages 539-552. March 1993.
Abstract: This paper suggets a new subclass of Petri net, POC net, as a superclass of AC nets and DC nets. For this subclass the equivalence between liveness and place-liveness is shown. Then the result is extended to liveness of timed Petri net under the earliest firing rule.