@misc{indiciaee895b7314e16,
  title = {Progress on Small Mercury Ion Clock for Space Applications},
  author = {Prestage, John D. and Chung, Sang K. and Thompson, Robert J. and MacNeal, Paul},
  year = {2009},
  url = {https://ntrs.nasa.gov/citations/20150008438},
  note = {Source identifier: 20150008438}
}