Nguyễn , Duy. 2025. “A SURVEY OF QUESTION TYPES IN ELEMENTARY-LEVEL VIETNAMESE LANGUAGE TEXTBOOKS FOR FOREIGN LEARNERS: FREQUENCY OF OCCURRENCE AND EXPLANATION OF STRUCTURE AND MEANING”. HCMUE Journal of Science 22 (6). https://journal.hcmue.edu.vn/index.php/hcmuejos/article/view/5061.