@booklet {319, title = {Concurrent Generalized Petri Nets}, journal = {Computations with Markov Chains}, year = {1995}, month = {18 January}, pages = {359{\textendash}382}, publisher = {Kluwer Academic Publishers}, address = {Amsterdam}, author = {V.CATANIA and A.PULIAFITO and Marco Scarpa and L.VITA} }