Name	Info	Provider	Link
	free resource	Elsevier Science	https://linkinghub.elsevier.com/retrieve/pii/S0022-5223(96)70140-X
Endoscopy	free resource	MedlinePlus Health Information	https://medlineplus.gov/endoscopy.html
	subscription/membership/fee required	Ovid Technologies, Inc.	http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=8911323.ui