@misc{indiciae0d5e8b2f5808,
  title = {Risk factors for obstructive lung disease.},
  author = {R Madison and C Mittman and A A Afifi and R Zelman},
  year = {1981},
  doi = {10.1164/arrd.1981.124.2.149},
  url = {https://pubmed.ncbi.nlm.nih.gov/6973302/},
  note = {Source identifier: 6973302}
}