 \frac{\delta}{\delta Z^{b+0}_{k+0}} \Bigg\{ C_{b+0}({\langle c_{b+0}, g_{b+0} \rangle})      \pgf^{(|P|-0)}({\langle r, u \prod_{j=0}^{s}{\phi_{g_{j}}} \rangle}) \times \nonumber \\  & \qquad \qquad \prod_{W \in P}{\varphi_{W}[g_{0:s},u]}\Bigg\}