To cite poweRlaw in publications use:

  Colin S. Gillespie (2015). Fitting Heavy Tailed Distributions: The
  poweRlaw Package. Journal of Statistical Software, 64(2), 1-16. URL
  http://www.jstatsoft.org/v64/i02/.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Fitting Heavy Tailed Distributions: The {poweRlaw} Package},
    author = {Colin S. Gillespie},
    journal = {Journal of Statistical Software},
    year = {2015},
    volume = {64},
    number = {2},
    pages = {1--16},
    url = {http://www.jstatsoft.org/v64/i02/},
  }