Let $f:X\rightarrow B$ be a fibration satisfying Assumption 6.22 and let $F_{\bar{b}}=f^{-1}(\bar{b})$ be a smooth fibre. There is a basis $\gamma=(\gamma_{1},\gamma_{2},\gamma_{3})$ of $H_{1}(F_{\bar{b}},\mathbb{Z})$ and coordinates $(b_{1},b_{2},b_{3})$ on $B$ with respect to which the periods of $f^{\pm}:X^{\pm}\rightarrow B^{\pm}$ can be written

$$\begin{array}[]{l}\lambda_{1}^{\pm}=2\pi db_{1},\\ \lambda_{2}^{\pm}=dH^{\pm}+\lambda_{0},\\ \lambda_{3}^{\pm}=db_{3},\end{array}$$

where $\lambda_{0}=\arg(b_{1}+ib_{2})db_{1}+\log|b_{1}+ib_{2}|db_{2}$ and $H^{\pm}\in C^{\infty}(B^{\pm})$. Moreover, there is a fibre preserving symplectomorphism

$$\Theta^{\pm}:T^{\ast}B^{\pm}/\penalty\Lambda_{H^{\pm}}\rightarrow(X^{\#})^{\pm}$$

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where $\Lambda_{H^{\pm}}$ is the integral lattice generated by $\lambda_{1}^{\pm},\lambda_{2}^{\pm},\lambda_{3}^{\pm}$.