@misc{indiciaedd6a8a74c81c,
  title = {Black lung.},
  author = {P R Graze},
  year = {1970},
  doi = {10.1056/nejm197011052831917},
  url = {https://pubmed.ncbi.nlm.nih.gov/4248496/},
  note = {Source identifier: 4248496}
}