Yan, Sherry H.F., Huiyun Ge, and Yaqiu Zhang. “On a Refinement of Wilf-Equivalence for Permutations”. The Electronic Journal of Combinatorics 22, no. 1 (February 9, 2015): P1.20. Accessed March 15, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v22i1p20.