\begin{align} 
\begin{split} 
\hat{q}_{\omega_{l, n, k}}(\theta_{l, n}) &=  p^{(1)}_{l+1, \,n}  \, \mathcal{N}(\, \theta_{l, n}; \omega^{(1)}_{\,l, n, k}\, , \,  \sigma^2 \, I_{\text{dim} [\theta_{l, n}]}\,)\\
&+ \,  p^{(2)}_{l+1, \,n}  \, \mathcal{N}(\, \theta_{l, n}; \omega^{(2)}_{\,l, n, k}\, ,  \, \sigma^2 \, I_{\text{dim} [\theta_{l, n}]}\,),\\
\end{split}
\label{eq:BSDON_b}
\end{align}
