Hartono Kurnio Reihaneh Safavi-Naini Huaxiong Wang Efficient Revocation Schemes for Secure Multicast. 160-177 2001 conf/icisc/2001 ICISC http://link.springer.de/link/service/series/0558/bibs/2288/22880160.htm db/conf/icisc/icisc2001.html#KurnioSW01