To cite package 'federalregister' in publications use:

Thomas J. Leeper (2014). federalregister: Client package for the U.S. Federal Register API. R package version 0.1.

Corresponding BibTeX entry:

  @Manual{,
    title = {federalregister: Client package for the U.S. Federal
      Register API},
    author = {Thomas J. Leeper},
    year = {2014},
    note = {R package version 0.1},
  }