?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Hallam%2C+Susan&rft.aufirst=Susan&rft.aulast=Hallam&rft.issue=1&rft.issn=0305-5698&rft.date=2003&rft.pages=69-83&rft.title=Educational+Studies&rft.volume=29&rft.atitle=Ability+grouping+in+the+primary+school%3A+a+survey&rft.genre=article