To cite colorspace in publications use:

  Zeileis A, Fisher JC, Hornik K, Ihaka R, McWhite CD, Murrell P,
  Stauffer R, Wilke CO (2020). “colorspace: A Toolbox for Manipulating
  and Assessing Colors and Palettes.” _Journal of Statistical
  Software_, *96*(1), 1-49. doi:10.18637/jss.v096.i01
  <https://doi.org/10.18637/jss.v096.i01>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {{colorspace}: A Toolbox for Manipulating and Assessing Colors and Palettes},
    author = {Achim Zeileis and Jason C. Fisher and Kurt Hornik and Ross Ihaka and Claire D. McWhite and Paul Murrell and Reto Stauffer and Claus O. Wilke},
    journal = {Journal of Statistical Software},
    year = {2020},
    volume = {96},
    number = {1},
    pages = {1--49},
    doi = {10.18637/jss.v096.i01},
  }

If you use HCL-based color palettes, please cite:

  Zeileis A, Hornik K, Murrell P (2009). “Escaping RGBland: Selecting
  Colors for Statistical Graphics.” _Computational Statistics & Data
  Analysis_, *53*(9), 3259-3270. doi:10.1016/j.csda.2008.11.033
  <https://doi.org/10.1016/j.csda.2008.11.033>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Escaping {RGB}land: Selecting Colors for Statistical Graphics},
    author = {Achim Zeileis and Kurt Hornik and Paul Murrell},
    journal = {Computational Statistics \& Data Analysis},
    year = {2009},
    volume = {53},
    number = {9},
    pages = {3259--3270},
    doi = {10.1016/j.csda.2008.11.033},
  }

If you use HCL-based color palettes in meteorological visualizations,
please cite:

  Stauffer R, Mayr GJ, Dabernig M, Zeileis A (2009). “Somewhere over
  the Rainbow: How to Make Effective Use of Colors in Meteorological
  Visualizations.” _Bulletin of the American Meteorological Society_,
  *96*(2), 203-216. doi:10.1175/BAMS-D-13-00155.1
  <https://doi.org/10.1175/BAMS-D-13-00155.1>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Somewhere over the Rainbow: How to Make Effective Use of Colors in Meteorological Visualizations},
    author = {Reto Stauffer and Georg J. Mayr and Markus Dabernig and Achim Zeileis},
    journal = {Bulletin of the American Meteorological Society},
    year = {2009},
    volume = {96},
    number = {2},
    pages = {203--216},
    doi = {10.1175/BAMS-D-13-00155.1},
  }