00428nam a2200157Ia 450000500170000000800460001703700110006304000200007404100130009408400240010710000250013124500600015626000090021630000100022554600350023520250508163337.0008  250505s9999    xx            000 0 eng d  aTheses  aFEDLbengcFEDL  aeng2eng  a510.7, GUP/THqFEDL  aGupta Ramesh Chandra 0aBackwardness in mathematics and basic arithmetic skills  c1971  a304p.  aPH.D Thesis (Delhi University)