@misc{indiciae966f17290a8b,
  title = {US patent problems.},
  author = {W T MacCulloch},
  year = {1987},
  doi = {10.1038/sj.bdj.4806091},
  url = {https://pubmed.ncbi.nlm.nih.gov/3472550/},
  note = {Source identifier: 3472550}
}