Ponkaew, C. ., and N. . Lawson. “New Variance Estimators in the Presence of Nonresponse Under Unequal Probability Sampling, With Application to Fine Particulate Matter in Thailand”. Thailand Statistician, vol. 22, no. 1, Dec. 2023, pp. 76-101, https://ph02.tci-thaijo.org/index.php/thaistat/article/view/252224.