@misc{indiciae4b15b35a2dfa,
  title = {New shield for gamma-ray spectrometry},
  author = {Brar, S. S. and Gustafson, P. F. and Nelson, D. M.},
  year = {1969},
  url = {https://ntrs.nasa.gov/citations/19690000343},
  note = {Source identifier: 19690000343}
}