@inproceedings{Green_2007,
    doi = {10.1145/1265530.1265535},
    url = {https://doi.org/10.1145%2F1265530.1265535},
    year = {2007},
    month = {jun},
    publisher = {{ACM}},
    author = {Todd J. Green and Grigoris Karvounarakis and Val Tannen},
    title = {Provenance semirings},
    booktitle = {Proceedings of the twenty-sixth {ACM} {SIGMOD}-{SIGACT}-{SIGART} symposium on Principles of database systems}
}

@inproceedings{Green_2007, doi = {10.1145/1265530.1265535}, url = {https://doi.org/10.1145%2F1265530.1265535}, year = {2007}, month = {jun}, publisher = {{ACM}}, author = {Todd J. Green and Grigoris Karvounarakis and Val Tannen}, title = {Provenance semirings}, booktitle = {Proceedings of the twenty-sixth {ACM} {SIGMOD}-{SIGACT}-{SIGART} symposium on Principles of database systems} }