@article{Williams_1970,
    doi = {10.4153/cmb-1970-094-8},
    url = {https://doi.org/10.4153%2Fcmb-1970-094-8},
    year = {1970},
    month = {dec},
    publisher = {Canadian Mathematical Society},
    volume = {13},
    number = {4},
    pages = {519--526},
    author = {Kenneth S. Williams},
    title = {Integers of Biquadratic Fields},
    journal = {Canadian Mathematical Bulletin}
}

@article{Williams_1970, doi = {10.4153/cmb-1970-094-8}, url = {https://doi.org/10.4153%2Fcmb-1970-094-8}, year = {1970}, month = {dec}, publisher = {Canadian Mathematical Society}, volume = {13}, number = {4}, pages = {519--526}, author = {Kenneth S. Williams}, title = {Integers of Biquadratic Fields}, journal = {Canadian Mathematical Bulletin} }