@incollection{Gay_1999,
    doi = {10.1007/3-540-49099-x_6},
    url = {https://doi.org/10.1007%2F3-540-49099-x_6},
    year = {1999},
    publisher = {Springer Berlin Heidelberg},
    pages = {74--90},
    author = {Simon Gay and Malcolm Hole},
    title = {Types and Subtypes for Client-Server Interactions},
    booktitle = {Programming Languages and Systems}
}

@incollection{Gay_1999, doi = {10.1007/3-540-49099-x_6}, url = {https://doi.org/10.1007%2F3-540-49099-x_6}, year = {1999}, publisher = {Springer Berlin Heidelberg}, pages = {74--90}, author = {Simon Gay and Malcolm Hole}, title = {Types and Subtypes for Client-Server Interactions}, booktitle = {Programming Languages and Systems} }