@article{Okhotin_2010,
    doi = {10.1016/j.jcss.2009.08.002},
    url = {https://doi.org/10.1016%2Fj.jcss.2009.08.002},
    year = {2010},
    month = {may},
    publisher = {Elsevier {BV}},
    volume = {76},
    number = {3-4},
    pages = {251--266},
    author = {Alexander Okhotin},
    title = {Decision problems for language equations},
    journal = {Journal of Computer and System Sciences}
}

@article{Okhotin_2010, doi = {10.1016/j.jcss.2009.08.002}, url = {https://doi.org/10.1016%2Fj.jcss.2009.08.002}, year = {2010}, month = {may}, publisher = {Elsevier {BV}}, volume = {76}, number = {3-4}, pages = {251--266}, author = {Alexander Okhotin}, title = {Decision problems for language equations}, journal = {Journal of Computer and System Sciences} }