@article{11497,
  author = {P. Wilson},
  title = {The structure of a sunspot. IV: A Two-Dimensional Radiative Transfer Analysis of Center-Limb Intensity Profiles},
  year = {1968},
  journal = {Solar Physics},
  volume = {5},
  pages = {338-353},
  month = {Jan-11-1968},
  issn = {0038-0938},
  doi = {10.1007/BF00147146},
}