Oliver Obst Markus Rollmann Spark - A Generic Simulator for Physical Multi-agent Simulations. 243-257 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3187&spage=243 2004 conf/mates/2004 MATES db/conf/mates/mates2004.html#ObstR04