To cite package ‘rtf’ in publications use:

Schaffer ME (2019). rtf: Rich Text Format (RTF) Output. R package version 0.4-14, https://github.com/schaffman5/rtf.

Corresponding BibTeX entry:

  @Manual{,
    title = {rtf: Rich Text Format (RTF) Output},
    author = {Michael E. Schaffer},
    year = {2019},
    note = {R package version 0.4-14},
    url = {https://github.com/schaffman5/rtf},
  }