@article{Chatzikos:2169,
      author        = "Chatzikos, M. and  Ferland, G. J. and  Williams, R. J. R.
                       and  Porter, R. and  van Hoof, P. A. M.",
      title         = "{Effects of External Radiation Fields on Line
                       Emission—Application to Star-forming Regions}",
      year          = "2013",
}