Avgustinovich, Sergey, Sergey Kitaev, and Anna Taranenko. “On Five Types of Crucial Permutations With Respect to Monotone Patterns”. The Electronic Journal of Combinatorics 30, no. 1 (February 24, 2023): P1.40. Accessed March 27, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v30i1p40.