Paper
Alternation
Ashok K. Chandra, Dexter C. Kozen, et al.
Journal of the ACM
It is shown that for every finite-state automaton there exists an equivalent nondeterministic automaton with a planar state graph. However there exist finite-state automata with no equivalent deterministic automaton with a planar state graph. © 1976 Springer-Verlag.
Ashok K. Chandra, Dexter C. Kozen, et al.
Journal of the ACM
Ashok K. Chandra, Prabhakar Raghavan, et al.
Computational Complexity
Ashok K. Chandra
SIGMOD/PODS/ 1988
Gregory J. Chaitin, Marc A. Auslander, et al.
Computer Languages