@misc{indiciae53c9f27ec29d,
  title = {Principles of engineering design.},
  author = {R K Penny},
  year = {1970},
  doi = {10.1136/pgmj.46.536.344},
  url = {https://pubmed.ncbi.nlm.nih.gov/5476130/},
  note = {Source identifier: 5476130}
}