\[\mathbf{B}(z,\lambda)=\begin{bmatrix}\tfrac{1}{4}&0\\
0&-\tfrac{1}{4}\end{bmatrix}\lambda+\begin{bmatrix}0&u_{0}\\
u_{1}&0\end{bmatrix}\dfrac{1}{z}-\begin{bmatrix}v_{0}-\tfrac{1}{4}z&-v_{1}v_{0%
}\\
\ifrac{(v_{0}-\tfrac{1}{2}z)}{v_{1}}&\tfrac{1}{4}z-v_{0}\end{bmatrix}\frac{1}{%
z\lambda},\]