%0 Journal Article %A V. N. Popov %T Application of~functional integration to~the~derivation of~the~low-frequency asymptotic behaviour of~Green's functions and kinetic equations for~a~nonideal Bose~gas %J Teoretičeskaâ i matematičeskaâ fizika %D 1971 %P 90-108 %V 6 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/TMF_1971_6_1_a9/ %G ru %F TMF_1971_6_1_a9