To cite package ‘dichromat’ in publications use:

  Lumley T (2026). _dichromat: Color Schemes for Dichromats_. R package
  version 2.0-1, <https://codeberg.org/zeileis/dichromat>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {dichromat: Color Schemes for Dichromats},
    author = {Thomas Lumley},
    year = {2026},
    note = {R package version 2.0-1},
    url = {https://codeberg.org/zeileis/dichromat},
  }