AUTHOR=Annweiler Cédric , Beauchet Olivier TITLE=Vitamin D in Older Adults: The Need to Specify Standard Values with Respect to Cognition JOURNAL=Frontiers in Aging Neuroscience VOLUME=6 YEAR=2014 URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2014.00072 DOI=10.3389/fnagi.2014.00072 ISSN=1663-4365