To cite package ‘tm.plugin.mail’ in publications use:

  Feinerer I, Mauerer W, Hornik K (2024). _tm.plugin.mail: Text Mining
  E-Mail Plug-in_. R package version 0.3-1,
  <https://CRAN.R-project.org/package=tm.plugin.mail>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {tm.plugin.mail: Text Mining E-Mail Plug-in},
    author = {Ingo Feinerer and Wolfgang Mauerer and Kurt Hornik},
    year = {2024},
    note = {R package version 0.3-1},
    url = {https://CRAN.R-project.org/package=tm.plugin.mail},
  }