@misc{indiciae241309825768,
  title = {Recirculating cryogenic hydrogen maser.},
  author = {MD Hürlimann and WN Hardy and AJ Berlinsky and RW Cline},
  year = {1986},
  doi = {10.1103/physreva.34.1605},
  url = {https://pubmed.ncbi.nlm.nih.gov/9897434/},
  note = {Source identifier: 9897434}
}