Name	Info	Provider	Link
	subscription/membership/fee required	Ingenta plc	https://www.ingentaconnect.com/openurl?genre=article&issn=0020-8167&volume=64&issue=1&spage=21&aulast=Giacalone
	subscription/membership/fee required	Ovid Technologies, Inc.	http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=38146879.ui
	subscription/membership/fee required	Wolters Kluwer	https://dx.doi.org/10.1097/IIO.0000000000000510