00456nam a2200145 a 450000500170000000800410001702000180005805000280007610000230010424500850012726000390021230000160025144000270026765000160029420140412111244.0010417s19uu    xx            00    eng d  a0-590-30167-5  aTR(GS 513.21bC651 1980  aStudebaker, Gordon  aComputational skills A: addition /cby Gordon Studebaker and John W. Studebaker.  aNew York :bScholastic Inc,c1980.  a32p. ; ill.  aScholastic Skills Book  aMathematics