@misc{indiciae97a0406b71d9,
  title = {Smallpox--world changes and implications for eradication.},
  author = {F L Soper},
  year = {1966},
  doi = {10.2105/ajph.56.10.1652},
  url = {https://pubmed.ncbi.nlm.nih.gov/5951484/},
  note = {Source identifier: 5951484}
}