@misc{indiciaeb27190bd95cf,
  title = {Etching and bonding patterns in human sub-surface enamel.},
  author = {P J Crawford and D K Whittaker},
  year = {1977},
  doi = {10.1038/sj.bdj.4803989},
  url = {https://pubmed.ncbi.nlm.nih.gov/334201/},
  note = {Source identifier: 334201}
}