  It was proven in [B.-Y. Chen, F. Dillen, J. Van der Veken and L. Vrancken,
Curvature inequalities for Lagrangian submanifolds: the final solution, Differ.
Geom. Appl. 31 (2013), 808-819] that every Lagrangian submanifold $M$ of a
complex space form $\tilde M^{n}(4c)$ of constant holomorphic sectional
curvature $4c$ satisfies the following optimal inequality: \begin{align*}
\delta(2,n-2) \leq \frac{n^2(n-2)}{4(n-1)} H^2 + 2(n-2) c, \end{align*} where
$H^2$ is the squared mean curvature and $\delta(2,n-2)$ is a $\delta$-invariant
on $M$. In this paper we classify Lagrangian submanifolds of complex space
forms $\tilde M^{n}(4c)$, $n \geq 5$, which satisfy the equality case of this
inequality at every point.
