To cite package ‘rgdal’ in publications use:

  Bivand R, Keitt T, Rowlingson B (2023). _rgdal: Bindings for the
  'Geospatial' Data Abstraction Library_. R package version 1.6-7, ,
  <https://CRAN.R-project.org/package=rgdal>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {rgdal: Bindings for the 'Geospatial' Data Abstraction Library},
    author = {Roger Bivand and Tim Keitt and Barry Rowlingson},
    year = {2023},
    note = {R package version 1.6-7, },
    url = {https://CRAN.R-project.org/package=rgdal},
  }