To cite R in publications use:

Matzke N, Sidje R, Schmidt D (2013). rexpokit: R wrappers for EXPOKIT; other matrix functions. University of California, Berkeley, Berkeley, CA. NOTE: The EXPOKIT FORTRAN library was published in: Sidje, R.B. (1998). A Software Package for Computing Matrix Exponentials. ACM-Transactions on Mathematical Software, 24(1):130-156. http://tinyurl.com/bwa87rq ; Also, the rexpokit R package was first published in: Matzke, Nicholas J. (2013). Probabilistic historical biogeography: new models for founder-event speciation, imperfect detection, and fossils allow improved accuracy and model-testing. Frontiers of Biogeography, 5(4), 242-248. http://escholarship.org/uc/item/44j7n141 , http://phylo.wikidot.com/rexpokit.

A lot of time and effort in creating EXPOKIT and rexpokit, please cite it, Sidje (1998), and Matzke (2013) when using it for publication. See also ‘citation("pkgname")’ for citing R packages.

Corresponding BibTeX entry:

  @Manual{,
    title = {rexpokit: R wrappers for EXPOKIT; other matrix functions},
    author = {Nicholas J. Matzke and Roger B. Sidje and Drew Schmidt},
    organization = {University of California, Berkeley},
    address = {Berkeley, CA},
    year = {2013},
    note = {NOTE: The EXPOKIT FORTRAN library was published in: Sidje,
      R.B. (1998). A Software Package for Computing Matrix
      Exponentials.  ACM-Transactions on Mathematical Software,
      24(1):130-156.  http://tinyurl.com/bwa87rq ; Also, the rexpokit R
      package was first published in: Matzke, Nicholas J. (2013).
      Probabilistic historical biogeography: new models for
      founder-event speciation, imperfect detection, and fossils allow
      improved accuracy and model-testing. Frontiers of Biogeography,
      5(4), 242-248.  http://escholarship.org/uc/item/44j7n141 },
    url = {http://phylo.wikidot.com/rexpokit},
  }