@misc{indiciae4da22007b700,
  title = {Proposed distributed feedback crystal cavities for X-ray lasers},
  author = {Elachi, C. and Evans, G. and Grunthaner, F.},
  year = {1975},
  url = {https://ntrs.nasa.gov/citations/19750034830},
  note = {Source identifier: 19750034830}
}