?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.aufirst=H&rft.au=Eswaran%2C+H&rft.aulast=Eswaran&rft.date=1990&rft.title=The+Soil+Component+In+Sustainable+Agriculture&rft.genre=proceeding