To cite package ‘gtools’ in publications use:

Warnes G, Bolker B, Lumley T, Magnusson A, Venables B, Ryodan G, Moeller S (2025). gtools: Various R Programming Tools. R package version 3.9.6, https://github.com/r-gregmisc/gtools.

Corresponding BibTeX entry:

  @Manual{,
    title = {gtools: Various R Programming Tools},
    author = {Gregory R. Warnes and Ben Bolker and Thomas Lumley and
      Arni Magnusson and Bill Venables and Genei Ryodan and Steffen
      Moeller},
    year = {2025},
    note = {R package version 3.9.6},
    url = {https://github.com/r-gregmisc/gtools},
  }