?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Thorup-Kristensen%2C+K.&rft.aulast=Thorup-Kristensen&rft.aufirst=K.&rft.date=2007&rft.title=Effect+of+crop+management+practices+on+the+sustainability+and+environmental+impact+of+organic+and+low+input+food+production+systems&rft.genre=proceeding