Joan Feigenbaum Michael J. Freedman Tomas Sander Adam Shostack Privacy Engineering for Digital Rights Management Systems. 76-105 2001 conf/ccs/2001drm Digital Rights Management Workshop http://link.springer.de/link/service/series/0558/bibs/2320/23200076.htm db/conf/ccs/ccsdrm2001.html#FeigenbaumFSS01