To cite the paper that the R did package is based on:

  Ortiz-Villavicencio M, Sant'Anna P (2025). “Better Understanding
  Triple Differences Estimators.” _ArXiv_.
  <https://arxiv.org/abs/2505.09942>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Better Understanding Triple Differences Estimators},
    author = {Marcelo Ortiz-Villavicencio and Pedro H.C. Sant'Anna},
    year = {2025},
    journal = {ArXiv},
    url = {https://arxiv.org/abs/2505.09942},
  }

To cite the did R package:

  Ortiz-Villavicencio M, Sant'Anna P (2025). “triplediff: Triple
  Differences Estimators.” R package version 0.2.0,
  <http://marcelortiz.com/triplediff/>.

A BibTeX entry for LaTeX users is

  @Misc{,
    title = {triplediff: Triple Differences Estimators},
    author = {Marcelo Ortiz-Villavicencio and Pedro H.C. Sant'Anna},
    year = {2025},
    note = {R package version 0.2.0},
    url = {http://marcelortiz.com/triplediff/},
  }