@misc{indiciae05fcc1017c24,
  title = {Low-level immunity to rubella.},
  author = {R L Northrop and W M Gardner and W F Geittmann},
  year = {1972},
  doi = {10.1056/nejm197209212871214},
  url = {https://pubmed.ncbi.nlm.nih.gov/5055216/},
  note = {Source identifier: 5055216}
}