David R. Karger Matthias Ruhl Diminished Chord: A Protocol for Heterogeneous Subgroup Formation in Peer-to-Peer Networks. 288-297 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3279&spage=288 2004 conf/iptps/2004 IPTPS db/conf/iptps/iptps2004.html#KargerR04a