1. Ábrego BM, Fernández-Merchant S, Neubauer MG, Watkins W (2009) Sum of squares of degrees in a graph. J Inequal Pure Appl Math 10(64):1–69
2. Ahlswede R, Katona GOH (1978) Graphs with maximal number of adjacent pairs of edges. Acta Math Hungar 32:97–120
3. Ali A, Das K C, Akhter S On the extremal graphs for second Zagreb index with fixed number of vertices and cyclomatic number. In: Miskolc Mathematical Notes (accepted)
4. An M, Xiong L (2015) Some results on the difference of the Zagreb indices of a graph. Bull Aust Math Soc 92:177–186
5. An M, Das KC (2018) First Zagreb index, $$k$$-connectivity, $$\beta $$-deficiency and $$k$$-hamiltonicity of graph. MATCH Commun Math Comput Chem 80:141–151