@article{Gaubert1999373,
    Author = {Gaubert, St{\'e}phane and Giua, Alessandro},
    File = {Petri Net Languages and Infinite Subsets of Nm - Gaubert, Giua (0) (0) - a - a - w.pdf},
    ISSN = {0022-0000},
    Journal = {Journal of Computer and System Sciences},
    Number = {3},
    Pages = {373 - 391},
    Title = {Petri Net Languages and Infinite Subsets of Nm},
    URL = {http://www.sciencedirect.com/science/article/pii/S0022000099916343},
    Volume = {59},
    Year = {1999},
    bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/S0022000099916343},
    bdsk-url-2 = {http://dx.doi.org/10.1006/jcss.1999.1634},
    date-added = {2013-09-25 10:32:05 +0000},
    date-modified = {2013-09-25 10:32:05 +0000},
    doi = {10.1006/jcss.1999.1634}
}

@article{Gaubert1999373, Author = {Gaubert, St{\'e}phane and Giua, Alessandro}, File = {Petri Net Languages and Infinite Subsets of Nm - Gaubert, Giua (0) (0) - a - a - w.pdf}, ISSN = {0022-0000}, Journal = {Journal of Computer and System Sciences}, Number = {3}, Pages = {373 - 391}, Title = {Petri Net Languages and Infinite Subsets of Nm}, URL = {http://www.sciencedirect.com/science/article/pii/S0022000099916343}, Volume = {59}, Year = {1999}, bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/S0022000099916343}, bdsk-url-2 = {http://dx.doi.org/10.1006/jcss.1999.1634}, date-added = {2013-09-25 10:32:05 +0000}, date-modified = {2013-09-25 10:32:05 +0000}, doi = {10.1006/jcss.1999.1634} }