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It is shown that in the case of bipartite graphs, the incidence energy IE , introduced in a recent work [M. R. Jooyandeh, D. Kiani, M. Mirzakhah, {\it MATCH Commun. Math. Comput. Chem.}, preceding article] coincides with the previously studied Laplacian-energy like invariant, {\it LEL} [ J. Liu, B. Liu, {\it MATCH Commun. Math. Comput. Chem. } {\bf 59} (2008) 355-372]. In the case of non-bipartite graphs, $IE$ is equal to the quantity $LEL^{+}$ , calculated in an analogous manner as $LEL$ , but from the eigenvalues of the signless Laplacian matrix. Some other relations for $IE$ are pointed out.
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