Daniele Micciancio Saurabh Panjwani Optimal Communication Complexity of Generic Multicast Key Distribution. 153-170 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3027&spage=153 2004 conf/eurocrypt/2004 EUROCRYPT db/conf/eurocrypt/eurocrypt2004.html#MicciancioP04