To cite package ‘rms’ in publications use:

  Harrell Jr F (2026). _rms: Regression Modeling Strategies_. R package
  version 8.1-2, <https://github.com/harrelfe/rms>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {rms: Regression Modeling Strategies},
    author = {Frank E {Harrell Jr}},
    year = {2026},
    note = {R package version 8.1-2},
    url = {https://github.com/harrelfe/rms},
  }