@misc{indiciaea7f53f9243ac,
  title = {Levelling-sharpening in aged persons.},
  author = {W G Warren and J W Staines},
  year = {1974},
  doi = {10.2466/pr0.1974.35.1.181},
  url = {https://pubmed.ncbi.nlm.nih.gov/4421866/},
  note = {Source identifier: 4421866}
}