John Burns Heather J. Ruskin Network Topology in Immune System Shape Space. 1094-1101 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3038&spage=1094 2004 conf/iccS/2004-3 International Conference on Computational Science db/conf/iccS/iccS2004-3.html#BurnsR04