@misc{indiciaed88c0a04e7a4,
  title = {Smallpox vaccination.},
  author = {S Krugman and S L Katz},
  year = {1969},
  doi = {10.1056/nejm196911272812211},
  url = {https://pubmed.ncbi.nlm.nih.gov/5347840/},
  note = {Source identifier: 5347840}
}