To cite package ‘double.truncation’ in publications use:

  Emura T, Hu Y, Huang C (2024). _double.truncation: Analysis of
  Doubly-Truncated Data_. R package version 1.8,
  <https://CRAN.R-project.org/package=double.truncation>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {double.truncation: Analysis of Doubly-Truncated Data},
    author = {Takeshi Emura and Ya-Hsuan Hu and Chung-Yan Huang},
    year = {2024},
    note = {R package version 1.8},
    url = {https://CRAN.R-project.org/package=double.truncation},
  }