00347nam a2200121Ia 450000500170000000800410001708200150005810000180007324500690009126000320016030000080019265000250020020240814120936.0240813s9999||||xx |||||||||||||| ||und||  a372.83 NAY  aNayar, Devaki 0aAssessment of vocabulary difficulty in social studies text books  aNew DelhibN.C.E.R.T.c1966  a44p  aElementary education