Michele Curti Pierpaolo Degano Cosima Tatiana Baldari Causal pi-Calculus for Biochemical Modelling. 21-33 2003 conf/cmsb/2003 CMSB http://link.springer.de/link/service/series/0558/bibs/2602/26020021.htm db/conf/cmsb/cmsb2003.html#CurtiDB03