?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=A&rft.au=Billon%2C+A&rft.aulast=Billon&rft.pages=97-105&rft.issn=0034-8252&rft.title=Revista+de+Filosof%C3%ADa+de+la+Universidad+de+Costa+Rica&rft.issue=136&rft.atitle=Can+Fregeans+have+'I'-thoughts%3F&rft.volume=53&rft.date=May+2014&rft.genre=article