Comment on Sound Dispersion in Single-Component System

This paper was initiated by publication of Ref. [1] and can be considered as Comments on Ref. [1]. Authors of Ref. [1] investigate analytically the propagation of sound waves in one component monatomic gas (especially for the intermediate Knudses number region) using methods of local kinetic description in area where they are not applied in principal. [1] Napier D.G., Shizgal B.D. Sound Dispersion in Single-Component Systems. Physica A 387, 4099–4118 (2008)