?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Groves%2C+PD&rft.aufirst=PD&rft.aulast=Groves&rft.issn=1048-5104&rft.atitle=Shadow+matching%3A+Improved+GNSS+accuracy+in+Urban+canyons&rft.pages=14+-+18%2B27&rft.issue=2&rft.volume=23&rft.title=GPS+World&rft.date=2012&rft.genre=article