00410nam a2200145Ia 450000500170000000800460001703700120006304000210007504100130009608400220010910000270013124500420015826000490020030000150024920250508150236.0008  250505s9999    xx            000 0 eng d  aTextual  aFEDL bengcFEDL  aeng2eng  a511.07, BALqFEDL  aBallard Philip Boswood 0aTeaching the essentials of arithmetic  aLondon, UKbUniversity of London Pressc1928  axxiv,260p.