@article{Lyndon_1956,
    doi = {10.2307/1969611},
    url = {https://doi.org/10.2307%2F1969611},
    year = {1956},
    month = {mar},
    publisher = {{JSTOR}},
    volume = {63},
    number = {2},
    pages = {294},
    author = {Roger C. Lyndon},
    title = {The Representation of Relation Algebras, {II}},
    journal = {The Annals of Mathematics}
}

@article{Lyndon_1956, doi = {10.2307/1969611}, url = {https://doi.org/10.2307%2F1969611}, year = {1956}, month = {mar}, publisher = {{JSTOR}}, volume = {63}, number = {2}, pages = {294}, author = {Roger C. Lyndon}, title = {The Representation of Relation Algebras, {II}}, journal = {The Annals of Mathematics} }