@article{10.1109/SFCS.1978.6,
    Address = {Los Alamitos, CA, USA},
    Author = {Ladner, Richard E. and Lipton, Richard J. and Stockmeyer, Larry J.},
    ISSN = {0272-5428},
    Journal = {2013 IEEE 54th Annual Symposium on Foundations of Computer Science},
    Pages = {92-106},
    Publisher = {IEEE Computer Society},
    Title = {Alternating pushdown automata},
    Volume = {0},
    Year = {1978},
    bdsk-url-1 = {http://doi.ieeecomputersociety.org/10.1109/SFCS.1978.6},
    date-added = {2014-03-22 16:33:17 +0000},
    date-modified = {2014-03-22 16:33:17 +0000},
    doi = {10.1109/SFCS.1978.6}
}

@article{10.1109/SFCS.1978.6, Address = {Los Alamitos, CA, USA}, Author = {Ladner, Richard E. and Lipton, Richard J. and Stockmeyer, Larry J.}, ISSN = {0272-5428}, Journal = {2013 IEEE 54th Annual Symposium on Foundations of Computer Science}, Pages = {92-106}, Publisher = {IEEE Computer Society}, Title = {Alternating pushdown automata}, Volume = {0}, Year = {1978}, bdsk-url-1 = {http://doi.ieeecomputersociety.org/10.1109/SFCS.1978.6}, date-added = {2014-03-22 16:33:17 +0000}, date-modified = {2014-03-22 16:33:17 +0000}, doi = {10.1109/SFCS.1978.6} }