@misc{indiciae0ec62c3403cd,
  title = {High and low thrust mission analysis for a Mars exploration program},
  author = {Shepard, Kyle M. and Horsewood, Jerry and Suskin, Mark},
  year = {1990},
  url = {https://ntrs.nasa.gov/citations/19910031656},
  note = {Source identifier: 19910031656}
}