@conference{5204,
  author = {Judah Levine},
  title = {The NIST internet time service},
  year = {1993},
  publisher = {NASA},
  address = {Goddard Space Flight Center},
  url = {http://www.pttimeeting.org/archivemeetings/1993papers/Vol\%2025_44.pdf},
  note = {JILA Pub. 5133},
}