@misc{1189536,
  author = {Keith C Roe},
  title = {A dual channel, double heterodyned phase shift measurement system 110 MHz to 18 GHz:},
  year = {1973},
  month = {1973-01-01 05:01:00},
  publisher = {, National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NBS.IR.73-307},
  language = {en},
}