To cite gtfsio in publications use:

Herszenhut D, Poletti F, Padgham M (2021). gtfsio: Read and Write General Transit Feed Specification (GTFS) Files. doi: 10.5281/zenodo.5650829, https://doi.org/10.5281/zenodo.5650829.

Corresponding BibTeX entry:

  @Manual{,
    title = {gtfsio: Read and Write General Transit Feed Specification
      (GTFS) Files},
    author = {Daniel Herszenhut and Flavio Poletti and Mark Padgham},
    month = {nov},
    year = {2021},
    publisher = {Zenodo},
    version = {v1.0.0},
    doi = {10.5281/zenodo.5650829},
    url = {https://doi.org/10.5281/zenodo.5650829},
  }