000 00409nam a2200145Ia 4500
008 130223s9999 xx 000 0 und d
100 _aSmith, W.G., Heady, E.O.
245 _aUse of a dynamic model in programming optimum conservation farm plans on Ida-Mon
260 _aAmes
260 _c1960
300 _a467-488 p.
440 _aIowa Agricultural Experiment S
901 _pS1254
942 _cB
_2udc
999 _c136138
_d136138