Ponkaew, C., & Lawson, N. (2024). New Product Estimators for Population Mean Under Unequal Probability Sampling with Missing Data: A Case Study on the Number of New COVID-19 Patients. Thailand Statistician, 22(3), 634–656. retrieved from https://ph02.tci-thaijo.org/index.php/thaistat/article/view/254773