Stefan Edelkamp Shahid Jabbar Action Planning for Directed Model Checking of Petri Nets. 3-18 2006 149 Electr. Notes Theor. Comput. Sci. 2 http://dx.doi.org/10.1016/j.entcs.2005.07.023 db/journals/entcs/entcs149.html#EdelkampJ06