Andreas Tanner Gero Mühl A Combinatorial Exchange for Autonomous Traders. 26-36 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2738&spage=26 2003 conf/ecweb/2003 EC-Web db/conf/ecweb/ecweb2003.html#TannerM03