@misc{indiciaef7e16f347c67,
  title = {Proton maser gain.},
  author = {DL Ensley},
  year = {1989},
  doi = {10.1103/physreva.39.958},
  url = {https://pubmed.ncbi.nlm.nih.gov/9901329/},
  note = {Source identifier: 9901329}
}