?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Blum%2C+A&rft.aufirst=A&rft.aulast=Blum&rft.issn=1469-5146&rft.pages=29-36&rft.atitle=Comparative+productivity+and+drought+response+of+semi-tropical+hybrids+and+open-pollinated+varieties+of+sorghum&rft.volume=118&rft.issue=1&rft.title=Journal+of+Agricultural+Science&rft.date=1992&rft.genre=article