Ramón Béjar Cèsar Fernández Carles Mateu Nuria Pascual Bounding the Phase Transition on Edge Matching Puzzles. 80-85 2009 ISMVL http://doi.ieeecomputersociety.org/10.1109/ISMVL.2009.55 conf/ismvl/2009 db/conf/ismvl/ismvl2009.html#BejarFMP09