@misc{indiciae59ff1197f963,
  title = {Spatial frequency doubling: retinal or central?},
  author = {W Richards and T B Felton},
  year = {1973},
  doi = {10.1016/0042-6989(73)90190-9},
  url = {https://pubmed.ncbi.nlm.nih.gov/4763526/},
  note = {Source identifier: 4763526}
}