  The inclusive spectra of pions and kaons produced in $Be Be$ collisions as
functions of their transverse momentum $p_t$ at mid-rapidity are calculated
within the self-similarity approach. A satisfactory description of NA61/SHINE
data on these spectra and the ratio of $K^\pm$ to $\pi^\pm$ meson production
cross sections in $Be Be$ collisions as a function of $\sqrt{s}$ are presented.
The similarity of these observables to the ones for $pp$ collisions at
mid-rapidity and in the wide range of initial energies is illustrated.
