To cite package ‘fdid’ in publications use:

  Xu Y, Lipkovitz R, Liu E (2026). _fdid: Factorial
  Difference-in-Differences_. R package version 1.0.2,
  <https://github.com/xuyiqing/fdid>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {fdid: Factorial Difference-in-Differences},
    author = {Yiqing Xu and Rivka Lipkovitz and Enhan Liu},
    year = {2026},
    note = {R package version 1.0.2},
    url = {https://github.com/xuyiqing/fdid},
  }