On Local Symmetries and Universality in Cellular Automata.

Laurent Boyer Guillaume Theyssier On Local Symmetries and Universality in Cellular Automata. 195-206 2009 STACS http://drops.dagstuhl.de/opus/volltexte/2009/1836 conf/stacs/2009 db/conf/stacs/stacs2009.html#BoyerT09