@inproceedings{Valero_Ruiz,
    doi = {10.1109/pnpm.1999.796565},
    url = {https://doi.org/10.1109%2Fpnpm.1999.796565},
    publisher = {{IEEE} Comput. Soc},
    author = {V. Valero Ruiz and D. de Frutos Escrig and F. Cuartero Gomez},
    title = {On non-decidability of reachability for timed-arc Petri nets},
    booktitle = {Proceedings 8th International Workshop on Petri Nets and Performance Models (Cat. No.{PR}00331)}
}

@inproceedings{Valero_Ruiz, doi = {10.1109/pnpm.1999.796565}, url = {https://doi.org/10.1109%2Fpnpm.1999.796565}, publisher = {{IEEE} Comput. Soc}, author = {V. Valero Ruiz and D. de Frutos Escrig and F. Cuartero Gomez}, title = {On non-decidability of reachability for timed-arc Petri nets}, booktitle = {Proceedings 8th International Workshop on Petri Nets and Performance Models (Cat. No.{PR}00331)} }