@misc{indiciaece2711ce0d46,
  title = {Comment on nondiffracting beams.},
  author = {P Sprangle and B Hafizi},
  year = {1991},
  doi = {10.1103/physrevlett.66.837},
  url = {https://pubmed.ncbi.nlm.nih.gov/10043913/},
  note = {Source identifier: 10043913}
}