TAPIA HERRERA, A. There is a Lack of Skills in Teachers for Teaching Mathematics in Upper Secondary Education. Universita Ciencia, [S. l.], v. 5, p. 139–146, 2016. DOI: 10.5281/zenodo.7158174. Disponível em: https://universita.ux.edu.mx/universita-ciencia/article/view/1209. Acesso em: 14 nov. 2026.