To cite package 'muRL' in publications use:

Moore, Ryan T. and Andrew Reeves (2013). muRL: Mailmerge using R, LateX, and the Web. R package version 0.1-9.

Corresponding BibTeX entry:

  @Manual{,
    title = {muRL: Mailmerge using R, LateX, and the Web},
    author = {Ryan T. Moore and Andrew Reeves},
    year = {2013},
    note = {R package version 0.1-9},
  }