@misc{indiciae8b35c2a91291,
  title = {Spatial-frequency masking and Birdsall's theorem.},
  author = {R A Smith and D J Swift},
  year = {1985},
  doi = {10.1364/josaa.2.001593},
  url = {https://pubmed.ncbi.nlm.nih.gov/4045590/},
  note = {Source identifier: 4045590}
}