?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=B&rft.au=Shiferaw%2C+B&rft.aulast=Shiferaw&rft.atitle=Rural+market+imperfections+and+the+role+of+institutions+in+collective+action+to+improve+markets+for+the+poor&rft.title=Natural+Resources+Forum&rft.date=2008&rft.volume=32&rft.pages=25-38&rft.issue=1&rft.genre=article