@misc{indiciaecb6dd529491a,
  title = {Note on Projective Coördinates.},
  author = {H P Robertson},
  year = {1928},
  doi = {10.1073/pnas.14.2.153},
  url = {https://pubmed.ncbi.nlm.nih.gov/16577103/},
  note = {Source identifier: 16577103}
}