@misc{indiciae071c210ffe12,
  title = {Second premolar extraction in Class I and Class II.},
  author = {L R Logan},
  year = {1973},
  doi = {10.1016/0002-9416(73)90068-7},
  url = {https://pubmed.ncbi.nlm.nih.gov/4509194/},
  note = {Source identifier: 4509194}
}