On the Seidel integral graphs which belong to the class αKa,a ∪ βKb,b

We say that a simple graph G is Seidel integral if its spectrum consists entirely of integers. If ?Ka,a ? ?Kb,b integral, we show it belongs the class graphs [kt/? x0 + mt/?z]Ka,a y0 a/?z]nKb,b, where (i) = (t+?n)k+?m and b ?m; (ii) t, k, ?,m, n N such (m, n) 1, (n, t) 1 (?, 1; (iii) (a,mt) | kt; (iv) (x0, y0) particular solution linear Diophantine equation ax (mt)y (v) z z0 least integer (kt/? mt/?z0)? a/?z0) 1. In particular, demonstrate ?Ka ?Kb in respect to ordinary adjacency matrix only integral.