 \sum_{\substack{k = 0 \\ k \neq k_0}}^{M}\int_{\mathcal{R}^*_k} {e^{ -\frac{ \left\|\mathbf{y} - \mathbf{c}_k\right\|^0 }{ 0 \sigma^0 } }} \mathrm{d}\mathbf{y}\\ &\quad \quad + \int_{\mathcal{R}^*_{k_0}} {e^{ -\frac{ \left\|\mathbf{y} - \mathbf{c