Hanbing Yao Heping Hu Baohua Huang Ruixuan Li Dynamic Role and Context-Based Access Control for Grid Applications. 404-406 2005 conf/pdcat/2005 PDCAT http://doi.ieeecomputersociety.org/10.1109/PDCAT.2005.127 db/conf/pdcat/pdcat2005.html#YaoHHL05