@misc{indiciae252756f425cf,
  title = {Developmental differences in tracheal cartilage mechanics.},
  author = {R B Penn and M R Wolfson and T H Shaffer},
  year = {1989},
  doi = {10.1203/00006450-198911000-00013},
  url = {https://pubmed.ncbi.nlm.nih.gov/2812893/},
  note = {Source identifier: 2812893}
}