Name	Info	Provider	Link
	subscription/membership/fee required	Ovid Technologies, Inc.	http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=11442591.ui
	subscription/membership/fee required	Wiley	https://onlinelibrary.wiley.com/resolve/openurl?genre=article&sid=nlm:pubmed&issn=1076-0512&date=2001&volume=27&issue=6&spage=549
	subscription/membership/fee required	Wolters Kluwer	https://doi.org/10.1046/j.1524-4725.2001.00360.x