%0 Journal Article %A D. N. Zubarev %A V. P. Kalashnikov %T Perturbation theory and integral equations for nonequilibrium statistical operators %J Teoretičeskaâ i matematičeskaâ fizika %D 1970 %P 406-416 %V 5 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/TMF_1970_5_3_a7/ %G ru %F TMF_1970_5_3_a7