He, Chaobing. “VERIFICATION OF SEVERAL IMPORTANT THEOREMS IN SIMPLE RANDOM SAMPLING USING R SOFTWARE”. Journal of Advance Research in Mathematics and Statistics (ISSN 2208-2409) 8, no. 12 (December 31, 2021): 01–07. Accessed September 12, 2025. https://textitlejournal.com/nnpub.org/index.php/MS/article/view/1134.