Chuzo Iwamoto Tomonobu Hatsuyama Kenichi Morita Katsunobu Imai On Time-Constructible Functions in One-Dimensional Cellular Automata. 316-326 http://link.springer.de/link/service/series/0558/bibs/1684/16840316.htm 1999 conf/fct/1999 FCT db/conf/fct/fct99.html#IwamotoHMI99