@misc{indiciae0ccae97b0947,
  title = {Advanced Space Propulsion: A Research Perspective},
  author = {Litchford, Ron and Cole, John and Rodgers, Steve and Sackheim, Bob},
  year = {2002},
  url = {https://ntrs.nasa.gov/citations/20030054539},
  note = {Source identifier: 20030054539}
}