Nodal cluster solutions for the Brezis-Nirenberg problem in dimensions $N\geq 7$

We show that the classical Brezis-Nirenberg problem $$\Delta u + |u|^{4 \over N-2} u + \varepsilon u = 0 ,\quad {\mbox {in}} \quad \Omega, \quad u= 0 , \quad {\mbox {on}} \quad \partial \Omega$$ admits nodal solutions clustering around a point on the boundary of $\Omega$ as $\varepsilon \to 0$, for smooth bounded domains $\Omega \subset \mathbb{R}^N$ in dimensions $N\geq 7$.