ShamsArmіn. “Re-Extending Chebyshev’s Theorem about Bertrand’s Conjecture”. Ukrains’kyi Matematychnyi Zhurnal 59, no. 12 (December 25, 2007): 1701–1706. Accessed July 27, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/3424.