1. A computer oriented toward spatial problems;Unger;Proc. IRE,1958
2. Pattern detection and recognition;Unger;Proc. IRE,1959
3. Recognition of Topological Invariants by Iterative Arrays;Beyer,1970
4. Two-dimensional formal languages and pattern recognition by cellular automata;Smith,1971
5. Theory of Self-Reproducing Automata;von Neumann,1966