@misc{indiciae2cd0205facc4,
  title = {A question of numbers.},
  author = {I S Loudon},
  year = {1976},
  doi = {10.1016/s0140-6736(76)93104-4},
  url = {https://pubmed.ncbi.nlm.nih.gov/56546/},
  note = {Source identifier: 56546}
}