To cite the elliptic package in publications use:

Robin K. S. Hankin (2006). “Introducing elliptic, an R package for elliptic and modular functions.” Journal of Statistical Software, 15.

Corresponding BibTeX entry:

  @Article{,
    title = {{Introducing elliptic, an R package for elliptic and
      modular functions}},
    author = {{Robin K. S. Hankin}},
    journal = {Journal of Statistical Software},
    year = {2006},
    month = {February},
    volume = {15},
    issue = {7},
  }