@article{8937,
  author = {David Hummer},
  title = {A fast and accurate method for evaluating the nonrelativistic free-free Gaunt factor for hydrogenic ions},
  year = {1988},
  journal = {The Astrophysical Journal},
  volume = {327},
  pages = {477},
  month = {Jan-04-1988},
  issn = {0004-637X},
  url = {http://articles.adsabs.harvard.edu/full/1988ApJ...327..477H},
  doi = {10.1086/166210},
}