@misc{indiciaef306646005fc,
  title = {The necessity for bidirectional views.},
  author = {F J Marshall},
  year = {1967},
  doi = {10.1016/0030-4220(67)90144-2},
  url = {https://pubmed.ncbi.nlm.nih.gov/5226441/},
  note = {Source identifier: 5226441}
}