To cite pbdMPI in a publication use:

Chen, W.-C., Ostrouchov, G., Schmidt, D., Patel, P., and Yu, H. (2012) pbdMPI: Programming with Big Data -- Interface to MPI. R Package, URL http://cran.r-project.org/package=pbdMPI
Chen, W.-C., Ostrouchov, G., Schmidt, D., Patel, P., and Yu, H. (2012) A Quick Guide for the pbdMPI Package. R Vignette, URL http://cran.r-project.org/package=pbdMPI

Corresponding BibTeX entries:

  @Misc{Chen2012pbdMPIpackage,
    title = {{pbdMPI}: Programming with Big Data -- Interface to
      {MPI}},
    author = {Wei-Chen Chen and George Ostrouchov and Drew Schmidt and
      Pragneshkumar Patel and Hao Yu},
    year = {2012},
    note = {{R} Package, URL http://cran.r-project.org/package=pbdMPI},
  }
  @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
      http://cran.r-project.org/package=pbdMPI},
  }