91: Hildesheimer Informatik-Berichte 3, pages 1-29 pp.. Universität Hildesheim (Germany), Institut für Informatik, April 1991.
Abstract: The paper introduces handles, a new tool for the analysis of Petri nets. Handles give mathematical content to some informal arguments frequently used by practitioners; they also provide sufficient conditions for liveness and boundedness of net systems. It is shown that these conditions are also necessary for a class containing all free choice Petri nets. A new proof of Hack's duality theorem is given.
Keywords: handles (in nets); (sufficient conditions for) liveness, boundedness; free choice net; Hack's duality theorem (new proof).