@misc{indiciaedf0ef49d2266,
  title = {Accurate, wide range ultrahigh-vacuum calibration system},
  author = {Brock, F. J. and Fowler, P.},
  year = {1970},
  url = {https://ntrs.nasa.gov/citations/19700066504},
  note = {Source identifier: 19700066504}
}