?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Frost%2C+David&rft.aulast=Frost&rft.aufirst=David&rft.date=2002&rft.title=Eight+years+of+organic+farming+at+Pwllpeiran+%C3%A2%C2%80%C2%93+livestock+production+and+the+financial+performance+of+organic+upland&rft.genre=proceeding