@misc{indiciaedd5c89ab63a6,
  title = {Letter: Pneumococcal antigen in sputum.},
  author = {R C Spencer and M A Savage},
  year = {1974},
  doi = {10.1016/s0140-6736(74)91294-x},
  url = {https://pubmed.ncbi.nlm.nih.gov/4133672/},
  note = {Source identifier: 4133672}
}