@inbook {IPMaMuSi87, title = {Modeling, Validation and Software Implementation of Production Systems Using High Level Petri Nets}, booktitle = {High-Level Petri Nets. Theory and Applications}, year = {1991}, pages = {618-623}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, address = {Berlin}, author = {J. Mart{\'\i}nez and P. Muro and M. Silva}, editor = {K. Jensen and G. Rozenberg} }