To cite package ‘PortinariColors’ in publications use:

  Lopes R (2026). _PortinariColors: Color Palettes Inspired by the
  Paintings of Candido Portinari_. R package version 0.3.0,
  <https://CRAN.R-project.org/package=PortinariColors>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {PortinariColors: Color Palettes Inspired by the Paintings of Candido Portinari},
    author = {Rafa Lopes},
    year = {2026},
    note = {R package version 0.3.0},
    url = {https://CRAN.R-project.org/package=PortinariColors},
  }