?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Hesketh%2C+Mark&rft.aulast=Hesketh&rft.aufirst=Mark&rft.date=2002&rft.title=The+use+of+case+studies+in+researching+the+conversion+to+organic+farming+systems&rft.genre=proceeding