@misc{indiciae0f5cf7ad08d7,
  title = {Pi/4-QPSK modems for satellite sound/data broadcast systems},
  author = {Liu, Chia-Liang and Feher, Kamilo},
  year = {1991},
  url = {https://ntrs.nasa.gov/citations/19910049331},
  note = {Source identifier: 19910049331}
}