Name	Info	Provider	Link
	free resource	Medknow Publications and Media Pvt Ltd	https://journals.lww.com/eusjournal/10.4103/eus.eus_60_18
	subscription/membership/fee required	Ovid Technologies, Inc.	http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=30785117.ui
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/30785117/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/30785117