?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.aufirst=Arega&rft.au=Alene%2C+Arega&rft.aulast=Alene&rft.date=2011&rft.title=Measuring+the+effectiveness+of+agricultural+R%26D+in+Sub-Saharan+Africa+from+the+perspectives+of+varietal+output+and+adoption+&rft.genre=proceeding