  Recently, Zabolotskii [Phys. Rev. E 77, 036603 (2008)] presented the Lax pair
for a version of the reduced Maxwell--Bloch equations. This version was derived
under considering the unidirectional propagation of a two-component
electromagnetic pulse through an anisotropic two-level medium. We demonstrate
that his derivation contains essential omission, which led to the wrong version
of the reduced Maxwell--Bloch equations. We also point out that the Lax pair
for correct version of these equations had been known in the most general
anisotropic case.
