@misc{indiciae79f3563db836,
  title = {Aetiological factors in persistent sputum production: a case-control study.},
  author = {P Cullinan},
  year = {1993},
  doi = {10.1136/jech.47.1.27},
  url = {https://pubmed.ncbi.nlm.nih.gov/8436888/},
  note = {Source identifier: 8436888}
}