%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 %U http://geodesic.mathdoc.fr/item/TMF_1971_6_1_a9/ %G ru %F TMF_1971_6_1_a9