“INFUSING A GAMIFICATION MECHANISM THROUGH DUOLINGO FOR ENGLISH SPEAKING PROFICIENCY: PERCEPTIONS OF THE INDONESIAN EFL INSTRUCTOR AND STUDENTS”. Konstruktivisme : Jurnal Pendidikan dan Pembelajaran 12, no. 1 (January 31, 2020): 69–80. Accessed January 7, 2026. https://ejournal.unisbablitar.ac.id/index.php/konstruktivisme/article/view/894.