@misc{indiciaeb44f07846c8b,
  title = {PROJECTIVE NORMAL COORDINATES.},
  author = {L P Eisenhart},
  year = {1930},
  doi = {10.1073/pnas.16.11.731},
  url = {https://pubmed.ncbi.nlm.nih.gov/16577301/},
  note = {Source identifier: 16577301}
}