To cite package ‘GUTS’ in publications use:

Albert C, Vogel S, Jakoby O, Singer A, Nickisch D (2025). GUTS: Fast Calculation of the Likelihood of a Stochastic Survival Model. R package version 1.2.6, https://CRAN.R-project.org/package=GUTS.

Corresponding BibTeX entry:

  @Manual{,
    title = {GUTS: Fast Calculation of the Likelihood of a Stochastic
      Survival Model},
    author = {Carlo Albert and Sören Vogel and Oliver Jakoby and
      Alexander Singer and Dirk Nickisch},
    year = {2025},
    note = {R package version 1.2.6},
    url = {https://CRAN.R-project.org/package=GUTS},
  }