Reference

      1. Gianfranco Balbo, "Introductory Tutorial Petri Nets", 21st International Conference on Application and Theory of Petri Nets.
      2. Elina Mancinelli, “On Traffic Light Control of Regular Towns", http://www-rocq.inria.fr/scilab/quadrat/transportRR.pdf
      3. Michael Weber, "Tool Support for Various Types of Petr Nets", Petri Net Technologies for Modelling Communication Based Systems, pages 171-178.
      4. Marc Boyer and Michel Diaz, "Multiple Enabledness of Transitions in Petri Nets with Time", 31077 Toulouse Cedex 4 France. [PS]
      5. Kurt Jensen, "A Brief Introduction to Coloured Petri Nets", Computer Science Department, University of Aarhus. [PDF]
      6. Bo Lindstrøm and Lisa Wells, "Annotating Coloured Petri Nets", Department of Computer Science, University of Aarhus. [PDF]