Luca Berardi Elena De Santis Maria Domenica Di Benedetto Invariant Sets and Control Synthesis for Switching Systems with Safety Specifications. 59-72 http://link.springer.de/link/service/series/0558/bibs/1790/17900059.htm 2000 conf/hybrid/2000 HSCC db/conf/hybrid/hscc2000.html#BerardiSB00