To cite package ‘geobr’ in publications use:

  Pereira R, Goncalves C (2024). _geobr: Download Official Spatial Data
  Sets of Brazil_. R package version 1.9.1, ,
  <https://github.com/ipeagit/geobr>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {geobr: Download Official Spatial Data Sets of Brazil},
    author = {Rafael H. M. Pereira and Caio Nogueira Goncalves},
    year = {2024},
    note = {R package version 1.9.1, },
    url = {https://github.com/ipeagit/geobr},
  }