?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.aufirst=C&rft.au=Schipmann%2C+C&rft.aulast=Schipmann&rft.date=2011&rft.title=Variety+Adoption+of+Orphan+Crops+by+Smallholder+Farmers+in+Tanzania+-+A+Survey+Based+Choice+Experiment&rft.genre=proceeding