KONGELF, T. R. What characterises the heuristic approaches in mathematics textbooks used in lower secondary schools in Norway?. NOMAD Nordic Studies in Mathematics Education, [S. l.], v. 16, n. 4, p. 5–44, 2011. DOI: 10.7146/nomad.v16i4.148407. Disponível em: https://tidsskrift.dk/NOMAD/article/view/148407. Acesso em: 8 jan. 2025.