To cite package 'rio' in publications use:

Chan C, Leeper T, Becker J, Schoch D (2023). rio: A Swiss-army knife for data file I/O. https://cran.r-project.org/package=rio.

Corresponding BibTeX entry:

  @Manual{,
    title = {rio: A Swiss-army knife for data file I/O},
    author = {Chung-hong Chan and Thomas J. Leeper and Jason Becker and
      David Schoch},
    url = {https://cran.r-project.org/package=rio},
    year = {2023},
  }