@misc{indiciae9f05e8a25e42,
  title = {Trapped-Mercury-Ion Frequency Standard},
  author = {Prestage, John D. and Dick, G. John and Maleki, Lutfollah},
  year = {1991},
  url = {https://ntrs.nasa.gov/citations/19910000257},
  note = {Source identifier: 19910000257}
}