@misc{indiciae6e676114dd3e,
  title = {Vaccination in density-dependent epidemic models.},
  author = {D Greenhalgh},
  year = {1992},
  doi = {10.1007/bf02459928},
  url = {https://pubmed.ncbi.nlm.nih.gov/1638258/},
  note = {Source identifier: 1638258}
}