Tong DH, Loc NP, Uyen BP, Giang LT. Developing the Competency of Mathematical Modelling: A Case Study of Teaching the Cosine and Sine Theorems. IJLTER [Internet]. 2019 Nov. 30 [cited 2026 Jun. 10];18(11):18-37. Available from: https://ijlter.myres.net/index.php/ijlter/article/view/437