Sangngam, Prayad, and Prachoom Suwattee. “Stratified Inverse Sampling for Rare Populations”. Thailand Statistician 10, no. 1 (May 27, 2015): 69–86. accessed April 8, 2025. https://ph02.tci-thaijo.org/index.php/thaistat/article/view/34233.