@conference {INDIN2007iopt, title = {{The Input-Output Place-Transition Petri Net Class and Associated Tools}}, booktitle = {5{\textsuperscript{th}} IEEE International Conference on Industrial Informatics (INDIN 2007).}, year = {2007}, note = {n/a}, month = {Jul.}, abstract = {n/a}, author = {Gomes, Lu{\'\i}s and {Jo{\~a}o Paulo} Barros and Anik{\'o} Costa and Ricardo Nunes} }