Some results on the complete sigraphs with exactly three non-negative eigenvalues

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[15] Z. Stanić, Some relations between the skew spectrum of an oriented graph and the spectrum of certain closely associated signed graphs, Rev. de la Union Mat. Argentina 63 (2022), no. 1, 41–50.  https://doi.org/10.33044/revuma.1914

[16] A. Torgašev, Graphs with exactly two negative eigenvalues, Math. Nachr. 122 (1985), no. 1, 135–140.  https://doi.org/10.1002/mana.19851220113

[17] T. Zaslavsky, Matrices in the theory of signed simple graphs, Advances in Discrete Mathematics and Applications, Ramanujan Mathematical Society Lecture Notes Series 13, Ramanujan Mathematical Society, Mysore, 2010, pp. 207–229.