@inproceedings{Sakoda_1978,
    doi = {10.1145/800133.804357},
    url = {https://doi.org/10.1145%2F800133.804357},
    year = {1978},
    publisher = {{ACM} Press},
    author = {William J. Sakoda and Michael Sipser},
    title = {Nondeterminism and the size of two way finite automata},
    booktitle = {Proceedings of the tenth annual {ACM} symposium on Theory of computing  - {STOC} {\textquotesingle}78}
}

@inproceedings{Sakoda_1978, doi = {10.1145/800133.804357}, url = {https://doi.org/10.1145%2F800133.804357}, year = {1978}, publisher = {{ACM} Press}, author = {William J. Sakoda and Michael Sipser}, title = {Nondeterminism and the size of two way finite automata}, booktitle = {Proceedings of the tenth annual {ACM} symposium on Theory of computing - {STOC} {\textquotesingle}78} }