Ruggero Lanotte Andrea Maggiolo-Schettini Adriano Peron Structural Model Checking for Communicating Hierarchical Machines. 525-536 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3153&spage=525 2004 conf/mfcs/2004 MFCS db/conf/mfcs/mfcs2004.html#LanotteMP04