@misc{indiciae541ea9d942cc,
  title = {Nitrogen abundance in Comet Halley},
  author = {Wyckoff, Susan and Tegler, Stephen C. and Engel, Lisa},
  year = {1991},
  url = {https://ntrs.nasa.gov/citations/19910038076},
  note = {Source identifier: 19910038076}
}