ສີສຸລາດ ທ. ສອນເພັດ, et al. “Year 7 Students’ Problems in the Use of Lao Language. A Case Study of Students in a Secondary School in Champasak Province ”. Champasack University Scientific Journal, vol. 4, no. 4, July 2020, pp. 111-22, http://cu-journal.com/index.php/files/article/view/36.