Ruiz de Gauna Gorostiza, Josu, Paulí Dávila Balsera, Juan Etxeberria Murgiondo, and Joxemari Sarasua Fernández. “The Mathematics Textbooks of High School in the Period 1970-2005”. Revista Latinoamericana de Investigación en Matemática Educativa 16, no. 2 (July 13, 2023): 245–276. Accessed October 23, 2026. https://www.relime.org/index.php/relime/article/view/222.