00409nam a2200145Ia 4500008004100000082001400041100002200055245003300077260003500110300000800145650004100153650003400194653001300228653002200241170901s1980    xx            000 0 und d  a631bC19B  aCarlson, Peter S. 0aBiology of Crop Productivity  aNew YorkbAcademic Pressc1980  a471  aAgriculture and related technologies  aTechnology (Applied sciences)  aAgronomy  aCrop productivity