To cite tmap/tmaptools in publications use:

  Tennekes M, Puts MJH (2023). “cols4all: a color palette analysis
  tool.” In _EuroVis (Short Papers)_. doi:10.2312/evs.20231040
  <https://doi.org/10.2312/evs.20231040>.

A BibTeX entry for LaTeX users is

  @InProceedings{,
    title = {{cols4all}: a color palette analysis tool},
    author = {Martijn Tennekes and Marco J. H. Puts},
    booktitle = {EuroVis (Short Papers)},
    publisher = {Wiley},
    doi = {10.2312/evs.20231040},
    year = {2023},
  }