@misc{indiciae2f37378ad4bf,
  title = {Density effect in K-shell ionization by relativistic electron impact.},
  author = {SC McDonald and BM Spicer},
  year = {1988},
  doi = {10.1103/physreva.37.985},
  url = {https://pubmed.ncbi.nlm.nih.gov/9899746/},
  note = {Source identifier: 9899746}
}