Munindar P. Singh Trustworthy Service Composition: Challenges and Research Questions. 39-52 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2631&spage=39 2002 conf/atal/2002lncs Trust, Reputation, and Security db/conf/atal/aamas2002lncs.html#Singh02