To cite package ‘phonenumber’ in publications use:

Myles S (2021). phonenumber: Convert Letters to Numbers and Back as on a Telephone Keypad. R package version 0.2.3, https://github.com/scumdogsteev/phonenumber.

Corresponding BibTeX entry:

  @Manual{,
    title = {phonenumber: Convert Letters to Numbers and Back as on a
      Telephone Keypad},
    author = {Steve Myles},
    year = {2021},
    note = {R package version 0.2.3},
    url = {https://github.com/scumdogsteev/phonenumber},
  }