To cite package 'msgtools' in publications use:

Thomas J. Leeper (2017). msgtools: Tools for Developing Diagnostic Messages. R package version 0.2.7.

Corresponding BibTeX entry:

  @Manual{,
    title = {msgtools: Tools for Developing Diagnostic Messages},
    author = {Thomas J. Leeper},
    year = {2017},
    note = {R package version 0.2.7},
  }