Manuel Koch Luigi V. Mancini Francesco Parisi-Presicce Foundations for a Graph-Based Approach to the Specification of Access Control Policies. 287-302 2001 conf/fossacs/2001 FoSSaCS http://dx.doi.org/10.1007/3-540-45315-6_19 db/conf/fossacs/fossacs2001.html#KochMP01