@article{6970,
  author = {M. Contini and B. Kozlovsky and G. Shav IV},
  title = {The calculation of the optical spectra of the Cygnus Loop},
  year = {1980},
  journal = {Astronomy and Astrophysics},
  volume = {92},
  pages = {273-280},
  url = {http://adsabs.harvard.edu/full/1980A\%26A....92..273C},
  note = {JILA Pub. 2085},
}