T. Khanyot, P. Sriraungrith, and S. Prachumchai, “THE RESULTS OF UTILIZING A CEFR-BASED ENGLISH LANGUAGE TRAINING PACKAGE TO IMPROVE ENGLISH PROFICIENCY LEVELS FOR 6 TH-GRADE STUDENTS ”, JPR, vol. 7, no. 1, pp. หน้า 224 – 236, Apr. 2024.