Javier Esparza Petr Jancar Alexander Miller On the Complexity of Consistency and Complete State Coding for Signal Transition Graphs. 47-56 2006 conf/acsd/2006 ACSD http://doi.ieeecomputersociety.org/10.1109/ACSD.2006.17 db/conf/acsd/acsd2006.html#EsparzaJM06