On the characterization of graphs with pendent vertices and given nullity. Liu, Bolian; Huang, Yufei; Chen, Siyuan — 2009 ELA. The Electronic Journal of Linear Algebra [electronic only]
Algebraic conditions for t -tough graphs Bo Lian Liu; Siyuan Chen — 2010 Czechoslovak Mathematical Journal We give some algebraic conditions for t -tough graphs in terms of the Laplacian eigenvalues and adjacency eigenvalues of graphs.