@misc{indiciaee88ef1f71195,
  title = {1981 LTA technology assessment - Past and present},
  author = {Ashford, R. L. and Levitt, B. B. and Mayer, N. J. and Vocar, J. M. and Woodward, D. E.},
  year = {1981},
  url = {https://ntrs.nasa.gov/citations/19810057508},
  note = {Source identifier: 19810057508}
}