Homotopy type of gauge groups of SU(3)-bundles over S6

Let Pk be the principal SU(3)-bundle over S6 with its Chern class c3(Pk)=2k. The purpose of this paper is to show when two gauge groups G(Pk) and G(Pk′) have the same homotopy type. Namely, G(Pk)≃G(Pk′), if and only if (120,k)=(120,k′), where (a,b) denote the G.C.D. of a and b.