?url_ver=Z39.88-2004&rft_id=doi%3A10.1785%2Fgssrl.75.1.82&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Bommer%2C+Julian+J.&rft.aulast=Bommer&rft.aufirst=Julian+J.&rft.issue=1&rft.volume=75&rft.date=2004&rft.issn=0895-0695&rft.atitle=The+Challenge+of+Defining+Upper+Bounds+on+Earthquake+Ground+Motions&rft.title=Seismological+Research+Letters&rft.pages=82-95&rft.genre=article