@misc{indiciae2a13b5a24efc,
  title = {Mars approach navigation using Doppler and range measurements to surface beacons and orbiting spacecraft},
  author = {Thurman, Sam W. and Estefan, Jeffrey A.},
  year = {1991},
  url = {https://ntrs.nasa.gov/citations/19930033918},
  note = {Source identifier: 19930033918}
}