WASET
    Farooq Ahmad and  Hejiao Huang and  Xiaolong Wang,  A Technique for Reachability Graph Generation for the Petri Net Models of Parallel Processes.   journal   = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2009, vol. 27(3). 811 - 815
    [viewed 24 April 2024]. Available from: https://publications.waset.org/pdf/14513.