@article{Brainerd_1968,
    doi = {10.1016/s0019-9958(68)90917-0},
    url = {https://doi.org/10.1016%2Fs0019-9958%2868%2990917-0},
    year = {1968},
    month = {nov},
    publisher = {Elsevier {BV}},
    volume = {13},
    number = {5},
    pages = {484--491},
    author = {Walter S. Brainerd},
    title = {The minimalization of tree automata},
    journal = {Information and Control}
}

@article{Brainerd_1968, doi = {10.1016/s0019-9958(68)90917-0}, url = {https://doi.org/10.1016%2Fs0019-9958%2868%2990917-0}, year = {1968}, month = {nov}, publisher = {Elsevier {BV}}, volume = {13}, number = {5}, pages = {484--491}, author = {Walter S. Brainerd}, title = {The minimalization of tree automata}, journal = {Information and Control} }