V. RANGAVENI. Element Invertibility and Structural Equivalence: A Task Analysis for Introductory Algebra. Journal of Statistics and Mathematical Engineering, [S. l.], v. 12, n. 3, p. 1–11, 2026. Disponível em: https://www.matjournals.net/engineering/index.php/JOSME/article/view/4144. Acesso em: 19 sep. 2026.