SAGALA, P.; TARIGAN, L.; PADANG, I.; LUMBANGAOL, D. . Workshop of Improving Teachers’ Competency in Teaching Speaking by Using Buzz Group at SMA Kristen Kalam Kudus Medan. . JURNAL ABDIMAS MADUMA, [S. l.], v. 1, n. 1, p. 77–88, 2022. DOI: 10.52622/jam.v1i1.100. Disponível em: https://www.journal.eltaorganization.org/index.php/ecdj/article/view/100. Acesso em: 18 apr. 2026.