4Dana L Kelly,Ina V.S.Mullis,Michael O.Martin.Profiles of Student Achievement in Mathematics at the TI MSS International Benchmarks:U.S.Performance and Standards in an International Context[]..2000
5National Council of Teachers of Mathematics(NCTM).Principles and Standards for School Mathematics. http://www.standards.nctm.org/documents . 2000
6OECD.Assessing Scientific,Reading and Mathematical Literacy.A Framework for PISA2006. http://www.pisa.oecd.org/pag-es/ . 2006