@article{Hack197677,
    Author = {Hack, Michel},
    File = {The equality problem for vector addition systems is undecidable - Hack (0) (0) - a - a - a.pdf},
    ISSN = {0304-3975},
    Journal = {Theoretical Computer Science},
    Keywords = {vector addition systems},
    Number = {1},
    Pages = {77 - 95},
    Title = {The equality problem for vector addition systems is undecidable},
    URL = {http://www.sciencedirect.com/science/article/pii/0304397576900086},
    Volume = {2},
    Year = {1976},
    bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/0304397576900086},
    bdsk-url-2 = {http://dx.doi.org/10.1016/0304-3975(76)90008-6},
    date-added = {2013-11-04 12:56:52 +0000},
    date-modified = {2013-11-04 12:57:16 +0000},
    doi = {10.1016/0304-3975(76)90008-6}
}

@article{Hack197677, Author = {Hack, Michel}, File = {The equality problem for vector addition systems is undecidable - Hack (0) (0) - a - a - a.pdf}, ISSN = {0304-3975}, Journal = {Theoretical Computer Science}, Keywords = {vector addition systems}, Number = {1}, Pages = {77 - 95}, Title = {The equality problem for vector addition systems is undecidable}, URL = {http://www.sciencedirect.com/science/article/pii/0304397576900086}, Volume = {2}, Year = {1976}, bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/0304397576900086}, bdsk-url-2 = {http://dx.doi.org/10.1016/0304-3975(76)90008-6}, date-added = {2013-11-04 12:56:52 +0000}, date-modified = {2013-11-04 12:57:16 +0000}, doi = {10.1016/0304-3975(76)90008-6} }