@misc{indiciae9cb60d571aef,
  title = {Internal jugular valves: competent or incompetent?},
  author = {S T Sum-Ping},
  year = {1994},
  doi = {10.1213/00000539-199406000-00001},
  url = {https://pubmed.ncbi.nlm.nih.gov/8198255/},
  note = {Source identifier: 8198255}
}