@misc{indiciae0a90857b515c,
  title = {Alkali metal propellants for MPD thrusters},
  author = {Polk, J. E. and Pivirotto, T. J.},
  year = {1991},
  url = {https://ntrs.nasa.gov/citations/19910067824},
  note = {Source identifier: 19910067824}
}