To cite package ‘pdftools’ in publications use:

  Ooms J (2024). _pdftools: Text Extraction, Rendering and Converting
  of PDF Documents_. R package version 3.4.1,
  <https://CRAN.R-project.org/package=pdftools>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {pdftools: Text Extraction, Rendering and Converting of PDF Documents},
    author = {Jeroen Ooms},
    year = {2024},
    note = {R package version 3.4.1},
    url = {https://CRAN.R-project.org/package=pdftools},
  }