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\[\mathbb{K}^{\mathbf{\text{uu}}}=\frac{\partial\mathbf{r}^{\mathbf{u}}}{\partial u}=\int_{\Omega}{g\left(\varphi,p\right)\mathbb{B}^{\mathbf{u}T}\mathbf{C}\mathbb{B}^{\mathbf{u}}d\Omega}\ ,\] \[\mathbb{K}^{\mathbf{u}\varphi}=\frac{\partial\mathbf{r}^{\mathbf{u}}}{\partial\varphi}=\int_{\Omega}{g_{,\varphi}\left(\varphi,p\right)\mathbb{B}^{\mathbf{u}T}\mathbf{\sigma}N^{T}}d\Omega\ ,\] \[\mathbb{K}^{\varphi\mathbf{u}}=\frac{\partial\mathbf{r}^{\varphi}}{\partial u}=\int_{\Omega}{g_{,\varphi}\left(\varphi,p\right)N\mathbf{\sigma}^{T}\mathbb{B}^{\mathbf{u}}}d\Omega\ ,\] \[\mathbb{K}^{\text{φφ}}=\frac{\partial\mathbf{r}^{\varphi}}{\partial\varphi}\int_{\Omega}{\mathcal{G}_{c}\mathcal{l}\mathbb{B}^{\text{φT}}\mathbb{B}^{\varphi}+\left[\frac{\mathcal{G}_{c}}{\mathcal{l}}+2\psi^{e}\left(\varepsilon\right)\right]NN^{T}}d\Omega\ ,\] The practical details in the Assembling algorithm for matrices are discussed in Appendix A.