Name	Info	Provider	Link
Endoscopy	free resource	MedlinePlus Health Information	https://medlineplus.gov/endoscopy.html
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19623479/
	subscription/membership/fee required	Springer	https://dx.doi.org/10.1007/s00464-009-0629-6
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/19623479