Martínez, Genaro J.; Seck-Tuoh-Mora, Juan C.; Zenil, Hector (2013), "Computation and Universality: Class IV versus Class III Cellular Automata", Journal of Cellular Automata, 7 (5–6): 393–430, arXiv:1304.1242, Bibcode:2013arXiv1304.1242M.
Martínez, Genaro J.; Seck-Tuoh-Mora, Juan C.; Zenil, Hector (2013), "Computation and Universality: Class IV versus Class III Cellular Automata", Journal of Cellular Automata, 7 (5–6): 393–430, arXiv:1304.1242, Bibcode:2013arXiv1304.1242M.