Alberto Dennunzio Pierre Guillon Benoît Masson Stable Dynamics of Sand Automata. 157-169 2008 IFIP TCS http://dx.doi.org/10.1007/978-0-387-09680-3_11 conf/ifipTCS/2008 db/conf/ifipTCS/ifipTCS2008.html#DennunzioGM08