Connectivity of Cartesian products of graphs

Let κ(G)κ(G) be the connectivity of GG and G□HG□H the Cartesian product of GG and HH. We prove that for any nontrivial graphs GG and HH, κ(G□H)=min{κ(G)|H|,κ(H)|G|,δ(G□H)}κ(G□H)=min{κ(G)|H|,κ(H)|G|,δ(G□H)}.