MUHAMMAD MIFTAHUL HIA; MUHYIDIN, M. S.; SETYAWAN, W. H. THE EFFECTIVENESS OF USING DUOLINGO IN TEACHING VOCABULARY TO CAMP CLASS AT LANGUAGE CENTER. Celtic : A Journal of Culture, English Language Teaching, Literature and Linguistics, [S. l.], v. 11, n. 2, p. 293–305, 2024. DOI: 10.22219/celtic.v11i2.37562. Disponível em: https://ejournal.umm.ac.id/index.php/celtic/article/view/37562. Acesso em: 4 jun. 2026.