To cite pbdMPI in a publication use:

  Chen W, Ostrouchov G, Schmidt D, Patel P, Yu H (2022). “pbdMPI: R
  Interface to MPI.” R Package, URL
  https://cran.r-project.org/package=pbdMPI.

A BibTeX entry for LaTeX users is

  @Misc{Chen2022pbdMPIpackage,
    title = {{pbdMPI}: R Interface to {MPI}},
    author = {Wei-Chen Chen and George Ostrouchov and Drew Schmidt and Pragneshkumar Patel and Hao Yu},
    year = {2022},
    note = {{R} Package, URL https://cran.r-project.org/package=pbdMPI},
  }

  Chen W, Ostrouchov G, Schmidt D, Patel P, Yu H (2012). _A Quick Guide
  for the pbdMPI Package_. R Vignette, URL
  https://cran.r-project.org/package=pbdMPI.

A BibTeX entry for LaTeX users is

  @Manual{Chen2012pbdMPIvignette,
    title = {A Quick Guide for the {pbdMPI} Package},
    author = {Wei-Chen Chen and George Ostrouchov and Drew Schmidt and Pragneshkumar Patel and Hao Yu},
    year = {2012},
    note = {{R} Vignette, URL https://cran.r-project.org/package=pbdMPI},
  }