00275nam a2200133Ia 4500020000900000082000800009100002000017245004200037250001000079260003200089300000800121500000600129650000600135  aNULL  a510  aMitchell, W. R. 0aPractical Mathematics For Technicians  aFirst  aLondonbEvans Brothers Ltd.  a160  a0  a-