Name	Info	Provider	Link
	subscription/membership/fee required	Ovid Technologies, Inc.	http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=19458549.ui
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19458549/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/19458549
	subscription/membership/fee required	Silverchair Information Systems	https://academic.oup.com/jnen/article-lookup/doi/10.1097/NEN.0b013e3181a39b3f