Stuart Haber Bill G. Horne Joe Pato Tomas Sander Robert Endre Tarjan If Piracy Is the Problem, Is DRM the Answer? 224-233 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2770&spage=224 2003 conf/drm/2003 Digital Rights Management db/conf/drm/drm2003.html#HaberHPST03