@misc{indiciae2e4b647d3e98,
  title = {A simple approach to grey scale echography.},
  author = {R Railton and A J Hall},
  year = {1975},
  doi = {10.1259/0007-1285-48-575-921},
  url = {https://pubmed.ncbi.nlm.nih.gov/1218303/},
  note = {Source identifier: 1218303}
}