Luís Caires Behavioral and Spatial Observations in a Logic for the pi-Calculus. 72-89 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2987&spage=72 2004 conf/fossacs/2004 FoSSaCS db/conf/fossacs/fossacs2004.html#Caires04