@misc{indiciae3569c1607868,
  title = {A simple beam-splitter attachment for physiological oscilloscopes.},
  author = {R D Purves},
  year = {1973},
  doi = {10.1007/bf02478670},
  url = {https://pubmed.ncbi.nlm.nih.gov/4787939/},
  note = {Source identifier: 4787939}
}