@misc{indiciae4366eff3d64e,
  title = {Immunisation levels---need they all decline?},
  author = {A L Bussey and B S Holmes},
  year = {1977},
  doi = {10.1016/s0140-6736(77)90903-5},
  url = {https://pubmed.ncbi.nlm.nih.gov/72302/},
  note = {Source identifier: 72302}
}