To cite ufs in publications use:

Peters GY, Gruijters S (2021). ufs: A collection of utilities. R package version 0.4.5, https://r-packages.gitlab.io/ufs.

Corresponding BibTeX entry:

  @Manual{,
    title = {ufs: A collection of utilities},
    author = {Gjalt-Jorn Ygram Peters and Stefan Gruijters},
    year = {2021},
    note = {R package version 0.4.5},
    url = {https://r-packages.gitlab.io/ufs},
  }