@misc{indiciaebc11d8bb4114,
  title = {Planetary radar},
  author = {Shaffer, R. D. and Wolken, P. R. and Jurgens, R. F.},
  year = {1981},
  url = {https://ntrs.nasa.gov/citations/19810018611},
  note = {Source identifier: 19810018611}
}