Database Intrusion Detection Using Role Profiling with Role Hierarchy. - Garfield Zhiping Wu; Sylvia L. Osborn; Xin Jin (Secure Data Management, 2009)

Effective and Efficient Bitmaps for Access Control. - Garfield Zhiping Wu; Frank Wm. Tompa (DCC, 2014)

A Space-Efficient Data Structure for Fast Access Control in ECM Systems. - Garfield Zhiping Wu; Frank Wm. Tompa (SACMAT, 2016)