To cite package ‘mapsFinland’ in publications use:

  Haukka J (2023). _mapsFinland: Maps of Finland_. R package version
  0.2.2, <https://CRAN.R-project.org/package=mapsFinland>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {mapsFinland: Maps of Finland},
    author = {Jari Haukka},
    year = {2023},
    note = {R package version 0.2.2},
    url = {https://CRAN.R-project.org/package=mapsFinland},
  }