00489nam a2200145Ia 4500008004100000082001400041100002200055245010300077260004300180300000800223650004100231650003400272653001600306700002100322170901s1930    xx            000 0 und d  a633bH89C  aHughes, D. Harold 0aCrop Production Principles and PracticesbA Handbook of Information for the Student of Agriculture  aNew YorkbThe Macmillan Compannyc1930  a816  aAgriculture and related technologies  aTechnology (Applied sciences)  aField crops  aHenson, R. Edwin