@misc{indiciae6e601a83d600,
  title = {Classification of toothbrush stiffness by a dynamic method.},
  author = {J R Heath and H J Wilson},
  year = {1971},
  doi = {10.1038/sj.bdj.4802627},
  url = {https://pubmed.ncbi.nlm.nih.gov/5278907/},
  note = {Source identifier: 5278907}
}