1. Diagonal Theorems for Random Access Machines;Cook,1972
2. Stephen A. Cook, Linear Time Simulation of Deterministic Two-way Pushdown Automata, Proceedings of IFIP Congress 71, Foundations of Information Processing.
3. Peter Naur (ed.), Revised Report on the Algorithmic Language ALGOL 60, C.A.C.M. 6, 1 (1963), 1–17.
4. Computational complexity of random access stored program machines;Hartmanis;Mathematical Systems Theory,1971