@inproceedings{Ibarra:1977:UEP:1382431.1382537,
    Address = {Washington, DC, USA},
    Author = {Ibarra, Oscar H.},
    BookTitle = {Proceedings of the 18th Annual Symposium on Foundations of Computer Science},
    Pages = {74--81},
    Publisher = {IEEE Computer Society},
    Series = {SFCS '77},
    Title = {The Unsolvability of the Equivalence Problem for e-Free NGSM's with Unary Input (Output) Alphabet and Applications},
    URL = {http://dx.doi.org/10.1109/SFCS.1977.35},
    Year = {1977},
    acmid = {1382537},
    bdsk-url-1 = {http://dx.doi.org/10.1109/SFCS.1977.35},
    date-added = {2016-02-10 14:02:37 +0000},
    date-modified = {2016-02-10 14:02:37 +0000},
    numpages = {8},
    doi = {10.1109/SFCS.1977.35}
}

@inproceedings{Ibarra:1977:UEP:1382431.1382537, Address = {Washington, DC, USA}, Author = {Ibarra, Oscar H.}, BookTitle = {Proceedings of the 18th Annual Symposium on Foundations of Computer Science}, Pages = {74--81}, Publisher = {IEEE Computer Society}, Series = {SFCS '77}, Title = {The Unsolvability of the Equivalence Problem for e-Free NGSM's with Unary Input (Output) Alphabet and Applications}, URL = {http://dx.doi.org/10.1109/SFCS.1977.35}, Year = {1977}, acmid = {1382537}, bdsk-url-1 = {http://dx.doi.org/10.1109/SFCS.1977.35}, date-added = {2016-02-10 14:02:37 +0000}, date-modified = {2016-02-10 14:02:37 +0000}, numpages = {8}, doi = {10.1109/SFCS.1977.35} }