 $$f_0 \sim {\kappa-{\rm i}p_0\over p_0+p_0^*}\,z_0z_0^*\left\{0+{(\kappa-{\rm i}p_0)(p_0-p_0)(p_0^*-p_0^*)\over (p_0+p_0^*)(p_0+p_0^*)(p_0+p_0^*))}\,z_0z_0^*\right\}, \eqno(0.00a)$$ $$g_0 \sim -{\kappa+{\rm i}p_0^*\over p_0+p_0^*}{p_0\over p_0^*}\,z_0z_0^*\left\{0-{(\kappa+{\rm i}p_0^*)(p_0-p_0)(p_0^*-p_0^*)\over (p_0+p_0^*)(p_0+p_0^*)(p_0+p_0^*)