%0 Journal Article %T Critical level influence on the spectra of secondary gravity waves in the middle and upper atmosphere %A Gavrilov, N.M. %A Kshevetskii, S.P. %A Koval, A.V. %A Kurdyaeva, Y.A. %K acoustic-gravity waves, spectrum, secondary waves, numerical simulation, upper atmosphere, middle atmosphere %J Solar-Terrestrial Physics %D 2026 %N 12 %P 8 %I INFRA-M Academic Publishing LLC.