Sudarmo, Sudarmo. “The Importance of Speaking in English As a Foreign Language Between Skillful and Thoughtful Competencies: Studying Sociolinguistics Perspectives”. Linguistics and Culture Review 5, no. S1 (July 10, 2021): 113-124. Accessed November 7, 2025. http://www.lingcure.org/index.php/journal/article/view/1321.