?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aulast=Longley&rft.au=Longley%2C+PA&rft.aufirst=PA&rft.volume=28&rft.issue=1&rft.date=February+2004&rft.title=Progress+in+Human+Geography&rft.atitle=Geographical+Information+Systems%3A+on+modelling+and+representation&rft.issn=0309-1325&rft.pages=108-116&rft.genre=article