Redondo Duarte, S., & Navarro Asencio, E. (2018). Study on Math Performance in Spain from the Data of the PISA 2003 Report. A Hierarchic Model of Two Levels. REICE. Ibero-American Journal on Quality, Effectiveness and Change in Education, 5(3). https://doi.org/10.15366/reice2007.5.3.004