@misc{indiciae0e25a8605406,
  title = {High-aperture beams.},
  author = {C J Sheppard},
  year = {2001},
  doi = {10.1364/josaa.18.001579},
  url = {https://pubmed.ncbi.nlm.nih.gov/11444550/},
  note = {Source identifier: 11444550}
}