To cite package ‘proustr’ in publications use:

  Fay C (2019). _proustr: Tools for Natural Language Processing in
  French_. R package version 0.4.0,
  <https://github.com/colinfay/proustr>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {proustr: Tools for Natural Language Processing in French},
    author = {Colin Fay},
    year = {2019},
    note = {R package version 0.4.0},
    url = {https://github.com/colinfay/proustr},
  }