@article{Hennessy_1985,
    doi = {10.1145/2455.2460},
    url = {https://doi.org/10.1145%2F2455.2460},
    year = {1985},
    month = {jan},
    publisher = {Association for Computing Machinery ({ACM})},
    volume = {32},
    number = {1},
    pages = {137--161},
    author = {Matthew Hennessy and Robin Milner},
    title = {Algebraic laws for nondeterminism and concurrency},
    journal = {Journal of the {ACM}}
}

@article{Hennessy_1985, doi = {10.1145/2455.2460}, url = {https://doi.org/10.1145%2F2455.2460}, year = {1985}, month = {jan}, publisher = {Association for Computing Machinery ({ACM})}, volume = {32}, number = {1}, pages = {137--161}, author = {Matthew Hennessy and Robin Milner}, title = {Algebraic laws for nondeterminism and concurrency}, journal = {Journal of the {ACM}} }