00309nam a2200121Ia 4500008004100000082001800041100002100059245004600080250001200126260002800138300001000166650001100176060110s9999    xx            000 0 und d  a512.72bDUD/E  aDUDLY, Underwood  aElementary number theorycUnderwood dudly  a2nd ed.  bWH Freeman and Coc1969  a249p.  a512.72