To cite package ‘epp’ in publications use:

  Eaton J (2023). _epp: R Implementation of the EPP model for HIV
  epidemic estimates._. R package version 0.4.4,
  <https://github.com/jeffeaton/epp>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {epp: R Implementation of the EPP model for HIV epidemic estimates.},
    author = {Jeff Eaton},
    year = {2023},
    note = {R package version 0.4.4},
    url = {https://github.com/jeffeaton/epp},
  }