Issue No.09 - September (1970 vol.19)
D. Tsichritzis , Dept. of Computer Sci. University of Toronto
The equivalence of the hierarchies of predicates or classes of sets is obtained. One hierarchy is given in terms of abstract machines, the other is defined in terms of the predicate calculus and involves formulas without quantifiers.
D. Tsichritzis, "R70-35 Classes of Automata and Transitive Closure", IEEE Transactions on Computers, vol.19, no. 9, pp. 858-859, September 1970, doi:10.1109/T-C.1970.223063