ZhiWu Li MengChu Zhou Naiqi Wu A Survey and Comparison of Petri Net-Based Deadlock Prevention Policies for Flexible Manufacturing Systems. 173-188 2008 38 IEEE Transactions on Systems, Man, and Cybernetics, Part C 2 http://dx.doi.org/10.1109/TSMCC.2007.913920 db/journals/tsmc/tsmcc38.html#LiZW08