Yuqing Sun 0001 Xiangxu Meng Fang Yin A Novel Approach for Role Hierarchies in Flexible RBAC Workflow. 488-491 2006 conf/edoc/2006 EDOC https://doi.org/10.1109/EDOC.2006.11 https://doi.ieeecomputersociety.org/10.1109/EDOC.2006.11 db/conf/edoc/edoc2006.html#SunMY06