@misc{indiciaed72a276b4b2e,
  title = {How large the umbrella?},
  author = {J W Beeler},
  year = {1976},
  doi = {10.1148/118.3.735},
  url = {https://pubmed.ncbi.nlm.nih.gov/1251033/},
  note = {Source identifier: 1251033}
}