\[b_{\beta}b_{\gamma}I(\mathbf{e}_{\alpha})=d_{\alpha\beta}d_{\alpha\gamma}I(-%
\mathbf{e}_{\alpha})+2b_{\alpha}\left(\frac{s(x)}{a_{\alpha}+b_{\alpha}x}-%
\frac{s(y)}{a_{\alpha}+b_{\alpha}y}\right),\]