?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aulast=Brown&rft.aufirst=Gavin&rft.au=+Brown+Gavin&rft.volume=67&rft.issn=0001-6969&rft.pages=221-247&rft.title=Acta+scientiarum+mathematicarum&rft.atitle=Positivity+of+a+class+of+cosine+sums&rft.date=2001&rft.issue=1-2&rft.genre=article