?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=M&rft.aulast=Sakr&rft.au=Sakr%2C+M&rft.pages=51-70&rft.date=8+January+2014&rft.atitle=The+Semiotic+Work+of+the+Hands+in+Scientific+Enquiry&rft.title=Classroom+Discourse&rft.issue=1&rft.volume=5&rft.genre=article