@misc{indiciae683abe20f687,
  title = {Optimizing Parking Orbits for Roundtrip Mars Missions},
  author = {Qu, Min and Merill, Raymond G. and Chai, Patrick and Komar, David R.},
  year = {2017},
  url = {https://ntrs.nasa.gov/citations/20170008844},
  note = {Source identifier: 20170008844}
}