@misc{indiciaed9229313647f,
  title = {A high-gain self-steering microwave repeater.},
  author = {Birgenheier, R. A. and Kummer, W. H.},
  year = {1968},
  url = {https://ntrs.nasa.gov/citations/19690047305},
  note = {Source identifier: 19690047305}
}