To cite package ‘icpack’ in publications use:

  Putter H, Eilers P (2024). _icpack: Survival Analysis of
  Interval-Censored Data_. R package version 0.1.0,
  <https://CRAN.R-project.org/package=icpack>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {icpack: Survival Analysis of Interval-Censored Data},
    author = {Hein Putter and Paul Eilers},
    year = {2024},
    note = {R package version 0.1.0},
    url = {https://CRAN.R-project.org/package=icpack},
  }