00543nam a2200169Ia 4500008004100000020001500041082001600056100002300072245011500095260003200210300000700242650004100249650003400290653002600324653001300350653001000363170901s1975    xx            000 0 und d  a0851983405  a631.4bR63S  aRobinson, J. B. D. 0aSoil Nitrogen Index And Its Calibration With Crop Performance to improve Fertilizer Efficiency on Arable Soils  aBureauxbCommonwealthc1975  a53  aAgriculture and related technologies  aTechnology (Applied sciences)  aFertilizer efficiency  aNitrogen  aSoils