Corrections to generalized Petri net reduction method

A reduction method for Petri nets was previously proposed by the authors (ibid., vol.SMC-15, pp. 272-80, Mar. 1985). In the present paper they give a modification of the reduction method that better conserves the Petri net property. Specifically, an example is shown in which two of the reduction rules do not conserve the liveness property. It is these two reduction rules that have been modified. The modified reduction method is useful for both ordinary and generalized nets.