@misc{indiciae694fce0a2ab9,
  title = {Stereoscopic comparator. Wtih primary use for optic discs.},
  author = {D D Donaldson and W M Grant},
  year = {1978},
  doi = {10.1001/archopht.1978.03910050271017},
  url = {https://pubmed.ncbi.nlm.nih.gov/629690/},
  note = {Source identifier: 629690}
}