@misc{indiciae4c3c876a191e,
  title = {Projective invariance and picture perception.},
  author = {K K Niall and J Macnamara},
  year = {1990},
  doi = {10.1068/p190637},
  url = {https://pubmed.ncbi.nlm.nih.gov/2102998/},
  note = {Source identifier: 2102998}
}