00287nam a2200097Ia 4500008004100000082001700041100003700058245004500095260004100140300000800181140113s9999    xx            000 0 und d  a631.371   K8  a"Blair, Byron. O. & Geyer, R.E."  aCurrent concepts for agronomic education  a1968bAmerican Soc. AgronomycU.S.A.  a160