@misc{indiciaea6bbb4f09cff,
  title = {[Root canal preparation using sonic-activated instruments].},
  author = {A Petschelt and H Oberschachtsiek and W Raab},
  year = {1987},
  url = {https://pubmed.ncbi.nlm.nih.gov/3471462/},
  note = {Source identifier: 3471462}
}