@misc{indiciaef523b9ddc7f5,
  title = {O I concentration in Comet Halley},
  author = {Smith, W. Hayden and Schempp, W. V.},
  year = {1989},
  url = {https://ntrs.nasa.gov/citations/19900028274},
  note = {Source identifier: 19900028274}
}