  We give an optimal upper bound for the anti-canonical volume of an
$\epsilon$-lc weak log del Pezzo surface. Moreover, we consider the relation
between the bound of the volume and the Picard number of the minimal resolution
of the surface. Furthermore we consider blowing up several points on a
Hirzebruch surface in general position and give some examples of smooth weak
log del Pezzo surfaces.

Algebraic Geometry