@article{4403,
  author = {W. Rammacher and M. Cuntz},
  title = {Effects of Mg II and Ca II ionization on ab-initio solar chromosphere models},
  year = {1990},
  journal = {Astronomy and Astrophysics},
  volume = {250},
  pages = {212-219},
  url = {http://articles.adsabs.harvard.edu/full/1991A\%26A...250..212R},
  note = {JILA Pub. 4355},
}