  The well-known shock solutions of the Korteweg-de Vries-Burgers equation are
revisited, together with their limitations in the context of plasma
(astro)physical applications. Although available in the literature for a long
time, it seems to have been forgotten in recent papers that such shocks are
monotonic and unique, for a given plasma configuration, and cannot show
oscillatory or bell-shaped features. This uniqueness is contrasted to solitary
wave solutions of the two parent equations (Korteweg-de Vries and Burgers),
which form a family of curves parameterized by the excess velocity over the
linear phase speed.
