Guo, Victor J. W. “Proof of Sun’s Conjecture on the Divisibility of Certain Binomial Sums”. The Electronic Journal of Combinatorics 20, no. 4 (November 22, 2013): P20. Accessed March 17, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v20i4p20.