The Extent of Using the Teachers of Mathematics at the Secondary Level in Aden Governorate for School Mathematics Operations Standards (NCTM). Humanities and Educational Sciences Journal, [S. l.], n. 43, p. 581–610, 2025. DOI: 10.55074/hesj.vi43.1257. Disponível em: http://hesj.org/ojs/index.php/hesj/article/view/1257. Acesso em: 30 may. 2026.