%0 Journal Article %A A. T. Il'ichev %T Effective wavelength of envelope waves on the water surface beneath an ice sheet: small amplitudes and moderate depths %J Teoretičeskaâ i matematičeskaâ fizika %D 2021 %P 387-408 %V 208 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/TMF_2021_208_3_a1/ %G ru %F TMF_2021_208_3_a1