@misc{indiciae6d2188a890e1,
  title = {An exposure meter for the electron microscope.},
  author = {E H FREI and F L HIRSHFELD},
  year = {1951},
  doi = {10.1063/1.1745897},
  url = {https://pubmed.ncbi.nlm.nih.gov/14854366/},
  note = {Source identifier: 14854366}
}