M. Fischer André Windisch Stefan Förster B. Balser Dieter Monjau A New Time Extension to phi-Calculus based on Time Consuming Transition Semantics. 447-456 2003 FDL http://www.ecsi-association.org/ecsi/main.asp?l1=library&fn=def&id=829 conf/fdl/2003 db/conf/fdl/fdl2003.html#FischerWFBM03