Claudio Agostino Ardagna Ernesto Damiani Sabrina De Capitani di Vimercati Pierangela Samarati Towards Privacy-Enhanced Authorization Policies and Languages. 16-27 2005 conf/dbsec/2005 DBSec http://dx.doi.org/10.1007/11535706_2 db/conf/dbsec/dbsec2005.html#ArdagnaDVS05