Name Info Provider Link
subscription/membership/fee required Ingenta plc https://www.ingentaconnect.com/openurl?genre=article&issn=&volume=138&issue=3&spage=264&aulast=Greenwald
Medicare free resource MedlinePlus Health Information https://medlineplus.gov/medicare.html
subscription/membership/fee required Ovid Technologies, Inc. http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=36538355.ui
free resource Silverchair Information Systems https://pubs.asahq.org/anesthesiology/article-lookup/doi/10.1097/ALN.0000000000004477