To cite package ‘gsDesign’ in publications use:

  Anderson K (2026). _gsDesign: Group Sequential Design_. R package
  version 3.10.0, <https://CRAN.R-project.org/package=gsDesign>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {gsDesign: Group Sequential Design},
    author = {Keaven Anderson},
    year = {2026},
    note = {R package version 3.10.0},
    url = {https://CRAN.R-project.org/package=gsDesign},
  }