1.
Chen WY, Gao OX, Guo PL. Hook Length Formulas for Trees by Han’s Expansion. Electron. J. Combin. [Internet]. 2009May15 [cited 2026Mar.16];16(1):R62. Available from: https://www.combinatorics.org/ojs/index.php/eljc/article/view/v16i1r62