@article{9258,
  author = {C. Schrijver and J. Cote and C. Zwaan and S. Saar},
  title = {Relations between the photospheric magnetic field and the emission from the outer atmospheres of cool stars. I - The solar CA II K line core emission},
  year = {1989},
  journal = {The Astrophysical Journal},
  volume = {337},
  pages = {964},
  month = {Jan-02-1989},
  issn = {0004-637X},
  url = {http://articles.adsabs.harvard.edu/full/1989ApJ...337..964S},
  doi = {10.1086/167168},
}