Yoshiyasu Ishigami Sei'ichi Tani VC-dimensions of Finite Automata and Commutative Finite Automata with k Letters, n States. 123-134 1997 74 Discrete Applied Mathematics 2 http://dx.doi.org/10.1016/S0166-218X(96)00025-X db/journals/dam/dam74.html#IshigamiT97