Chen, John T., and SenetaE. М. “Multivariate Sobel–Uppuluri–Galambos-Type Bounds”. Ukrains’kyi Matematychnyi Zhurnal 52, no. 9 (September 25, 2000): 1283-1293. Accessed May 11, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/4535.