1. Adamatzky, A. (ed.): Collision-Based Computing. Springer, Heidelberg (2002); ISBN 1- 85233-540-8
2. Berlekamp, E.R., Conway, J.H., Guy, R.K.: Winning Ways for your Mathematical Plays, vol. 2, ch. 25. Academic Press, London (1982); ISBN 0-12-091152-3
3. Cook, M.: Universality in Elementary Cellular Automata. personal communication
4. Cook, M.: Introduction to the activity of rule 110 (copyright 1994-1998 Matthew Cook) (January 1999), http://w3.datanet.hu/~cook/Workshop/CellAut/Elementary/Rule110/110pics.html
5. Cook, M.: Still Life Theory. In: New Constructions in Cellular Automata (Santa Fe Institute Studies on the Sciences of Complexity), p. 93. Oxford University Press, Oxford (April 2003); ISBN 0-1951-3717-5