Branigan, Laura Adhi Pramadhika. “Teachers’ Roles in Applying Problem Solving Activity to Teach Speaking”. RETAIN : Journal of Research in English Language Teaching 10, no. 01 (June 4, 2022): 53–57. Accessed August 12, 2025. https://ejournal.unesa.ac.id/index.php/retain/article/view/41536.