1. S. Akbari, P.J. Cameron, G.B. Khosrovshahi, Ranks and signatures of adjacency matrices, submitted
2. The energy of a graph;Balakrishnan;Linear Algebra Appl.,2004
3. Algebriac Graph Theory;Biggs,1993
4. Recent Results in the Theory of Graph Spectra;Cvetković,1988
5. Spectra of Graphs Theory and Applications;Cvetković,1995