?url_ver=Z39.88-2004&rft_id=10.1016%2Fj.brainresbull.2009.01.013&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aulast=Ricciardi&rft.au=Ricciardi%2C+Emiliano&rft.aufirst=Emiliano&rft.issn=0361-9230&rft.pages=322+-+332&rft.issue=5&rft.volume=79&rft.date=30+June+2009&rft.title=Brain+Research+Bulletin&rft.atitle=Cholinergic+modulation+of+visual+working+memory+during+aging%3A+a+parametric+PET+study&rft.genre=article