@misc{indiciae839b66ed08c5,
  title = {Which PPI?},
  author = {M J Langman},
  year = {2001},
  doi = {10.1136/gut.49.2.309},
  url = {https://pubmed.ncbi.nlm.nih.gov/11454811/},
  note = {Source identifier: 11454811}
}