?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Frohberg%2C+K.&rft.aulast=Frohberg&rft.aufirst=K.&rft.date=1985&rft.isbn=0080325424&rft.title=Modeling+Agricultural+Production+for+Policy+Analysis&rft.btitle=Identification+and+System+Parameter+Estimation&rft.genre=bookitem