@misc{indiciae2ce0350d5558,
  title = {The Sobolev approximation for the line force and line source function in a spherically-symmetrical stellar wind with continuum opacity},
  author = {Puls, J. and Hummer, D. G.},
  year = {1988},
  url = {https://ntrs.nasa.gov/citations/19880040687},
  note = {Source identifier: 19880040687}
}