@misc{indiciaee3c8cdae2325,
  title = {Invariant Sequences.},
  author = {E T Bell},
  year = {1928},
  doi = {10.1073/pnas.14.12.901},
  url = {https://pubmed.ncbi.nlm.nih.gov/16587418/},
  note = {Source identifier: 16587418}
}