To cite package ‘qpdf’ in publications use:

  Ooms J (2024). _qpdf: Split, Combine and Compress PDF Files_. R
  package version 1.3.4, <https://github.com/ropensci/qpdf>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {qpdf: Split, Combine and Compress PDF Files},
    author = {Jeroen Ooms},
    year = {2024},
    note = {R package version 1.3.4},
    url = {https://github.com/ropensci/qpdf},
  }