To cite package ‘geotools’ in publications use:

  Burkhard P (2024). _geotools: Support for Geography Packages_. R
  package version 1.1.0.9000, <https://github.com/nenuial/geotools>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {geotools: Support for Geography Packages},
    author = {Pascal Burkhard},
    year = {2024},
    note = {R package version 1.1.0.9000},
    url = {https://github.com/nenuial/geotools},
  }