See Yan WONG. “Rethinking the Pedagogical Sequence of Trigonometric Formulae in Secondary Education : A Preliminary Assessment of an Alternative Teaching Approach in a Hong Kong Secondary ”. INTERNATIONAL JOURNAL OF MANAGEMENT RESEARCH AND REVIEW, vol. 16, no. 3, Sept. 2026, pp. 204-6, https://ijmrr.com/index.php/ijmrr/article/view/759.