@misc{indiciae7c6c5c1cd184,
  title = {The CfA Einstein Observatory extended deep X-ray survey},
  author = {Primini, F. A. and Murray, S. S. and Huchra, J. and Schild, R. and Burg, R.},
  year = {1991},
  url = {https://ntrs.nasa.gov/citations/19910056258},
  note = {Source identifier: 19910056258}
}