?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=A+J&rft.au=Duncan%2C+A+J&rft.aulast=Duncan&rft.atitle=Integrated+crop-livestock+systems+%E2%88%92+a+key+to+sustainable+intensification+in+Africa&rft.title=Tropical+Grasslands+%E2%80%93+Forrajes+Tropicales&rft.issn=2346-3775&rft.date=2013&rft.volume=1&rft.pages=202-206&rft.issue=2&rft.genre=article