Name	Info	Provider	Link
	subscription/membership/fee required	Nature Publishing Group	https://doi.org/10.1111/j.1745-7254.2007.00587.x
	subscription/membership/fee required	Ovid Technologies, Inc.	http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=17640482.ui
	subscription/membership/fee required	Wiley	https://onlinelibrary.wiley.com/resolve/openurl?genre=article&sid=nlm:pubmed&issn=1671-4083&date=2007&volume=28&issue=8&spage=1189