Naizhen Qi Michiharu Kudo Jussi Myllymaki Hamid Pirahesh A function-based access control model for XML databases. 115-122 2005 conf/cikm/2005 CIKM http://doi.acm.org/10.1145/1099554.1099577 db/conf/cikm/cikm2005.html#QiKMP05