Amaniarsih DS, Asrul N, Juliana J, Ginting E. THE EFFECTIVENESS OF USING THE DUOLINGGO APPLICATION IN IMPROVING STUDENTS’ MOTIVATION AND ENGLISH-SPEAKING SKILL AT UNIVERSITAS POTENSI UTAMA MEDAN. J. Pedagogi [Internet]. 14 Januari 2025 [dikutip 3 Maret 2025];11(1):46-54. Tersedia pada: http://siakad.univamedan.ac.id/ojs/index.php/pedagogi/article/view/933