00402nam a2200121Ia 4500008004100000082001900041100008500060245002300145260003200168300001500200490004900215650001600264140224s9999    xx            000 0 und d  a631.473(02) J1  aBureau of Plant Industry, Soils and Agricultural Engineering, Soil Survey Staff.  aSoil survey manual  aCalcuttabOxford, IBHc1951  aviii,503p.  aU.S. Department Agriculture, Handbook; no.18  aSoil survey