Ritthirak, K. ., P. . Saensuk, and K. Samart. “Comparison of regression coefficient estimates of linear mixed model on missing longitudinal data”. KKU Science Journal, vol. 48, no. 2, Nov. 2022, pp. 183-91, https://ph01.tci-thaijo.org/index.php/KKUSciJ/article/view/250090.