Tummalangka, P., and S. Sengsri. “The Effect of Using Learning Document with Augmented Reality Technology about Chinese Pinyin for Mattayomsuksa 4 Students”. ECT Education and Communication Technology Journal, vol. 16, no. 20, June 2021, pp. 49-60, https://so01.tci-thaijo.org/index.php/ectstou/article/view/243041.