@misc{indiciaec6c5de36eca7,
  title = {Programmed self-instruction in oral hygiene.},
  author = {D Bratthall},
  year = {1967},
  doi = {10.1111/j.1600-0765.1967.tb01891.x},
  url = {https://pubmed.ncbi.nlm.nih.gov/4237479/},
  note = {Source identifier: 4237479}
}