To cite package ‘pch’ in publications use:

  Frumento P (2025). _pch: Piecewise Constant Hazard Models for
  Censored and Truncated Data_. R package version 2.2,
  <https://CRAN.R-project.org/package=pch>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {pch: Piecewise Constant Hazard Models for Censored and Truncated Data},
    author = {Paolo Frumento},
    year = {2025},
    note = {R package version 2.2},
    url = {https://CRAN.R-project.org/package=pch},
  }