To cite package ‘highr’ in publications use:

  Xie Y, Qiu Y (2024). _highr: Syntax Highlighting for R Source Code_.
  R package version 0.11.1, <https://github.com/yihui/highr>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {highr: Syntax Highlighting for R Source Code},
    author = {Yihui Xie and Yixuan Qiu},
    year = {2024},
    note = {R package version 0.11.1},
    url = {https://github.com/yihui/highr},
  }