@article{Chomsky1959137,
    Author = {Chomsky, Noam},
    File = {On certain formal properties of grammars - Chomsky (0) (0) - a - a - y.pdf},
    ISSN = {0019-9958},
    Journal = {Information and Control},
    Number = {2},
    Pages = {137 - 167},
    Title = {On certain formal properties of grammars},
    URL = {http://www.sciencedirect.com/science/article/pii/S0019995859903626},
    Volume = {2},
    Year = {1959},
    bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/S0019995859903626},
    bdsk-url-2 = {http://dx.doi.org/10.1016/S0019-9958(59)90362-6},
    date-added = {2013-12-18 15:48:24 +0000},
    date-modified = {2013-12-18 15:48:24 +0000},
    doi = {10.1016/S0019-9958(59)90362-6}
}

@article{Chomsky1959137, Author = {Chomsky, Noam}, File = {On certain formal properties of grammars - Chomsky (0) (0) - a - a - y.pdf}, ISSN = {0019-9958}, Journal = {Information and Control}, Number = {2}, Pages = {137 - 167}, Title = {On certain formal properties of grammars}, URL = {http://www.sciencedirect.com/science/article/pii/S0019995859903626}, Volume = {2}, Year = {1959}, bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/S0019995859903626}, bdsk-url-2 = {http://dx.doi.org/10.1016/S0019-9958(59)90362-6}, date-added = {2013-12-18 15:48:24 +0000}, date-modified = {2013-12-18 15:48:24 +0000}, doi = {10.1016/S0019-9958(59)90362-6} }