Habtamu Abie Pål Spilling Bent Foyn Rights-Carrying and Self-enforcing Information Objects for Information Distribution Systems. 546-562 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3269&spage=546 2004 conf/icics/2004 ICICS db/conf/icics/icics2004.html#AbieSF04