TAUFIQ, Wahyu; NOVITA, Dian. Buku Ajar Speaking for formal Communication. Umsida Press, [S. l.], p. 1–59, 2022. DOI: 10.21070/2021/978-623-6292-32-7. Disponível em: https://press.umsida.ac.id/index.php/umsidapress/article/view/978-623-6292-32-7. Acesso em: 5 jul. 2025.