000 00434nam a2200121Ia 4500
008 140113s9999 xx 000 0 und d
082 _a631.811.3:581.19 L1
100 _aInternational Potash Institute
245 _aTransition from extensive to intensive agriculture with fertilizers :Proceedings of the 7th Colloquium International Potash Institute
260 _a1969
_bPotash Institute
_cSwitzerland
300 _a282
942 _cBK
999 _c58047
_d58047