?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=C+F&rft.au=Yamoah%2C+C+F&rft.aulast=Yamoah&rft.atitle=Use+of+rainfall+indices+to+analyze+the+effects+of+phosphate+rocks+on+millet+in+the+Sahel&rft.title=African+Journal+of+Agricultural+Research&rft.issn=1991-637X&rft.date=2011&rft.volume=6&rft.pages=586-593&rft.issue=3&rft.genre=article