00285nam a2200109Ia 4500008004100000082001900041100002100060245002900081260004200110300001000152650001300162140113s9999    xx            000 0 und d  a631(047.1 J2.4  a" Norman, A. G."  aAdvances in agronomy v.4  b"New York : Academic Press Inc, 1952"  a416p.  aAgronomy