| Name | Info | Provider | Link |
|---|---|---|---|
| Gastrointestinal Bleeding | free resource | MedlinePlus Health Information | https://medlineplus.gov/gastrointestinalbleeding.html |
| free resource | PubMed Central | https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/26693188/ | |
| free resource | Europe PubMed Central | https://europepmc.org/abstract/MED/26693188 |