Ayyer, Arvind, Robert Cori, and Dominique Gouyou-Beauchamps. “Monotone Triangles and 312 Pattern Avoidance”. The Electronic Journal of Combinatorics 18, no. 2 (November 7, 2011): P26. Accessed March 15, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v18i2p26.