@article{Kelly_1964,
    doi = {10.1016/0021-8693(64)90018-3},
    url = {https://doi.org/10.1016%2F0021-8693%2864%2990018-3},
    year = {1964},
    month = {dec},
    publisher = {Elsevier {BV}},
    volume = {1},
    number = {4},
    pages = {397--402},
    author = {G.M Kelly},
    title = {On MacLane's conditions for coherence of natural associativities, commutativities, etc.},
    journal = {Journal of Algebra}
}

@article{Kelly_1964, doi = {10.1016/0021-8693(64)90018-3}, url = {https://doi.org/10.1016%2F0021-8693%2864%2990018-3}, year = {1964}, month = {dec}, publisher = {Elsevier {BV}}, volume = {1}, number = {4}, pages = {397--402}, author = {G.M Kelly}, title = {On MacLane's conditions for coherence of natural associativities, commutativities, etc.}, journal = {Journal of Algebra} }