Li, Xueliang, and Yan Liu. “Nonexistence of Triples of Nonisomorphic Connected Graphs With Isomorphic Connected $P_3$-Graphs”. The Electronic Journal of Combinatorics 15, no. 1 (February 11, 2008): R31. Accessed March 16, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v15i1r31.