@misc{indiciae1ea8990db605,
  title = {Conditional Invariants.},
  author = {G Y Rainich},
  year = {1941},
  doi = {10.1073/pnas.27.7.352},
  url = {https://pubmed.ncbi.nlm.nih.gov/16578018/},
  note = {Source identifier: 16578018}
}