a) ^{e(k)}  ^{e(k′)}^{p(P)}  ^{p(P′)}^{V^{0}(V)}_{t}^{−Q^{2}}^{W}^{s}  ^{γ^{∗}(q)}  b) ^{e(k)}  ^{e(k′)}^{p(P)}  ^{M_{N}}^{V^{0}(V)}_{t}^{−Q^{2}}^{W}^{s}  ^{γ^{∗}(q)}