000 00282nam a2200121Ia 4500
008 170101s1980 xx 000 0 und d
082 _a631.5 CAR
100 _aCarlson Peter S.
245 4 _aThe Biology Crop Productivity
260 _c1980
300 _a471 p.
942 _2ddc
_cB
999 _c705166
_d705166