@misc{indiciaec8aecfad5bac,
  title = {A modified cross cylinder.},
  author = {J A EGAN},
  year = {1951},
  doi = {10.1001/archopht.1951.01700020159005},
  url = {https://pubmed.ncbi.nlm.nih.gov/14856475/},
  note = {Source identifier: 14856475}
}