@article{Manna_1970,
    doi = {10.1145/321592.321606},
    url = {https://doi.org/10.1145%2F321592.321606},
    year = {1970},
    month = {jul},
    publisher = {Association for Computing Machinery ({ACM})},
    volume = {17},
    number = {3},
    pages = {555--569},
    author = {Zohar Manna and Amir Pnueli},
    title = {Formalization of Properties of Functional Programs},
    journal = {Journal of the {ACM}}
}

@article{Manna_1970, doi = {10.1145/321592.321606}, url = {https://doi.org/10.1145%2F321592.321606}, year = {1970}, month = {jul}, publisher = {Association for Computing Machinery ({ACM})}, volume = {17}, number = {3}, pages = {555--569}, author = {Zohar Manna and Amir Pnueli}, title = {Formalization of Properties of Functional Programs}, journal = {Journal of the {ACM}} }