Reihaneh Safavi-Naini Yejing Wang A Combinatorial Approach to Asymmetric Traitor Tracing. 416-425 2000 conf/cocoon/2000 COCOON http://link.springer.de/link/service/series/0558/bibs/1858/18580416.htm db/conf/cocoon/cocoon2000.html#Safavi-NainiW00