?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Tomassini%2C+A&rft.aufirst=A&rft.aulast=Tomassini&rft.title=PLoS+One&rft.atitle=Which+way+is+down%3F+Positional+distortion+in+the+tilt+illusion.&rft.pages=+&rft.date=24+October+2014&rft.issue=10&rft.volume=9&rft.genre=article