To cite careless in publication use:

Yentes RD, Wilhelm F (2021). careless: Procedures for computing indices of careless responding. R package version 1.2.1.

Corresponding BibTeX entry:

  @Manual{,
    title = {careless: Procedures for computing indices of careless
      responding},
    author = {Richard D. Yentes and Francisco Wilhelm},
    year = {2021},
    note = {R package version 1.2.1},
  }