@misc{indiciae9c249edbd3ac,
  title = {Effect of defocus on visual acuity as measured by source and observer methods.},
  author = {G Smith and R J Jacobs and C D Chan},
  year = {1989},
  doi = {10.1097/00006324-198907000-00004},
  url = {https://pubmed.ncbi.nlm.nih.gov/2771329/},
  note = {Source identifier: 2771329}
}