To cite package ‘xfun’ in publications use:

Xie Y (2026). xfun: Supporting Functions for Packages Maintained by 'Yihui Xie'. R package version 0.58.1, https://github.com/yihui/xfun.

Corresponding BibTeX entry:

  @Manual{,
    title = {xfun: Supporting Functions for Packages Maintained by
      'Yihui Xie'},
    author = {Yihui Xie},
    year = {2026},
    note = {R package version 0.58.1},
    url = {https://github.com/yihui/xfun},
  }