00375nam a22001217a 4500020001500000040000900015082001600024100001800040245006600058250001600124260004700140650006600187  a9812530061  cNust  a515.35bBOY  aBoyce-Diprima  aElementary differential equations and boundary value problems  a7th Edition  aNew York:bJohn Wiley and sons Inc,c2003.  aElementary differential equations and boundary value problems