Sudakov, Benny, and Jacques Verstraete. “The Extremal Function for Cycles of Length $\ell$ Mod $k$”. The Electronic Journal of Combinatorics 24, no. 1 (January 20, 2017): #P1.7. Accessed May 13, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v24i1p7.