Name Info Provider Link
subscription/membership/fee required Ovid Technologies, Inc. http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=12941140.ui
free resource PubMed Central https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/12941140/
free resource Wiley https://onlinelibrary.wiley.com/resolve/openurl?genre=article&sid=nlm:pubmed&issn=0019-2805&date=2003&volume=110&issue=1&spage=48