@misc{indiciaea2996ff84657,
  title = {UAM Airspace Research Roadmap},
  author = {Ian Levitt and Nipa Phojanamongkolkij and Kevin Witzberger and Joseph Rios and Annie Cheng},
  year = {2021},
  url = {https://ntrs.nasa.gov/citations/20210019876},
  note = {Source identifier: 20210019876}
}