To cite package ‘etwfe’ in publications use:

  McDermott G (2025). _etwfe: Extended Two-Way Fixed Effects_. R
  package version 0.5.0.99, <https://github.com/grantmcdermott/etwfe>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {etwfe: Extended Two-Way Fixed Effects},
    author = {Grant McDermott},
    year = {2025},
    note = {R package version 0.5.0.99},
    url = {https://github.com/grantmcdermott/etwfe},
  }