@misc{indiciaeaf428c6125d7,
  title = {Activity-passivity.},
  author = {P Gray},
  year = {1967},
  doi = {10.1177/000306516701500312},
  url = {https://pubmed.ncbi.nlm.nih.gov/6052582/},
  note = {Source identifier: 6052582}
}