Title: Maximum and minimum operators of convex integrands,
Abstract: For given convex integrands $\gamma_{{}_{i}}: S^{n}\to \mathbb{R}_{+}$ (where
$i=1, 2$), the functions $\gamma_{{}_{max}}$ and $\gamma_{{}_{min}}$ can be
defined as natural way. In this paper, we show that the Wulff shape of
$\gamma_{{}_{max}}$ (resp. the Wulff shape of $\gamma_{{}_{min}}$) is exactly
the convex hull of $(\mathcal{W}_{\gamma_{{}_{1}}}\cup
\mathcal{W}_{\gamma_{{}_{2}}})$ (resp. $\mathcal{W}_{\gamma_{{}_{1}}}\cap
\mathcal{W}_{\gamma_{{}_{2}}}$).