TY - CONF AU - Shu-Fen Tu AU - Ching-Sheng Hsu BT - World Congress on Engineering, WCE 2007 CY - London, U.K. DA - July 2 - 4, 2007 LA - eng PP - London, U.K. PY - 2007 T2 - World Congress on Engineering, WCE 2007 TI - A VC-Based Copyright Protection Scheme for Digital Images of Multi-Authorship ER -