@misc{indiciae59c2e2659015,
  title = {Dose response of ipratropium assessed by two methods.},
  author = {C J Allen and A H Campbell},
  year = {1980},
  doi = {10.1136/thx.35.2.137},
  url = {https://pubmed.ncbi.nlm.nih.gov/6445607/},
  note = {Source identifier: 6445607}
}