Relationship between edge Szeged and edge Wiener indices of graphs

Let G be a connected graph and ξ(G) = Sze(G) - We(G), where We(G) denotes the edge Wiener index and Sze(G) denotes the edge Szeged index of G. In an earlier paper, it is proved that if T is a tree then Sze(T) = We(T). In this paper, we continue our work to prove that for every connected graph G, Sze(G) ≥ We(G) with equality if and only if G is a tree. We also classify all graphs with ξ(G) ≤ 5. Finally, for each non-negative integer n ≠ 1 there exists a graph G such that ξ(G) = n