@misc{indiciae075df6abd6a7,
  title = {Polarity signals.},
  author = {C R Hopkins},
  year = {1991},
  doi = {10.1016/0092-8674(91)90427-z},
  url = {https://pubmed.ncbi.nlm.nih.gov/1653646/},
  note = {Source identifier: 1653646}
}