@misc{indiciaefa48b8fbf298,
  title = {VEGA Pathfinder navigation for Giotto Halley encounter},
  author = {Ellis, J. and Mcelrath, T. P.},
  year = {1986},
  url = {https://ntrs.nasa.gov/citations/19870005923},
  note = {Source identifier: 19870005923}
}