@incollection{Cheng_1993,
    doi = {10.1007/3-540-57529-4_66},
    url = {https://doi.org/10.1007%2F3-540-57529-4_66},
    year = {1993},
    publisher = {Springer Berlin Heidelberg},
    pages = {326--337},
    author = {Allan Cheng and Javier Esparza and Jens Palsberg},
    title = {Complexity results for 1-safe nets},
    booktitle = {Lecture Notes in Computer Science}
}

@incollection{Cheng_1993, doi = {10.1007/3-540-57529-4_66}, url = {https://doi.org/10.1007%2F3-540-57529-4_66}, year = {1993}, publisher = {Springer Berlin Heidelberg}, pages = {326--337}, author = {Allan Cheng and Javier Esparza and Jens Palsberg}, title = {Complexity results for 1-safe nets}, booktitle = {Lecture Notes in Computer Science} }