Bounds on sombor index and inverse sum indeg (ISI) index of graph operations

Let G be a graph with vertex set V (G) and edge set E(G). Denote by d_G(u) the degree of a vertex u ∈ V (G). The Sombor index of G is defined as SO(G) = ^P_uv∈E(G₎^pd²_u + d²_v, whereas, the inverse sum indeg (ISI) index is defined as ISI(G) = ^P_uv∈E(G) _d^d_u^u₊^d_d^v_v . In this paper, we compute the bounds in terms of maximum degree, minimum degree, order and size of the original graphs G and H for Sombor and ISI indices of several graph operations like corona product, cartesian product, strong product, composition and join of graphs.