@article{Kraj_ek_1995,
    doi = {10.1002/rsa.3240070103},
    url = {https://doi.org/10.1002%2Frsa.3240070103},
    year = {1995},
    month = {aug},
    publisher = {Wiley},
    volume = {7},
    number = {1},
    pages = {15--39},
    author = {Jan Kraj{\'{\i}}{\v{c}}ek and Pavel Pudl{\'{a}}k and Alan Woods},
    title = {An exponential lower bound to the size of bounded depth frege proofs of the pigeonhole principle},
    journal = {Random Structures {\&} Algorithms}
}

@article{Kraj_ek_1995, doi = {10.1002/rsa.3240070103}, url = {https://doi.org/10.1002%2Frsa.3240070103}, year = {1995}, month = {aug}, publisher = {Wiley}, volume = {7}, number = {1}, pages = {15--39}, author = {Jan Kraj{\'{\i}}{\v{c}}ek and Pavel Pudl{\'{a}}k and Alan Woods}, title = {An exponential lower bound to the size of bounded depth frege proofs of the pigeonhole principle}, journal = {Random Structures {\&} Algorithms} }