00294nam a2200109Ia 450000500170000000800410001708200150005810000170007324500430009026000430013330000080017620260224041012.0260224s9999||||xx |||||||||||||| ||und||  a631.42 SIN  aSingh, S.S.  0aSoil fertility and nutrient management  aLudhiana : Kalyani Publications c2004  a253