Two-way finite automata with quantum and classical state

@article{Ambainis2002TwowayFA,
  title={Two-way finite automata with quantum and classical state},
  author={Andris Ambainis and John Watrous},
  journal={Theor. Comput. Sci.},
  year={2002},
  volume={287},
  pages={299-311}
}

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