%0 Journal Article %A È. Kh. Naziev %A G. I. Keleinikova %T Application of the theory of continuous transformation groups to the qualitative investigation of second order dynamical systems %J Differencialʹnye uravneniâ %D 1973 %P 381-382 %V 9 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1973_9_2_a26/ %G ru %F DE_1973_9_2_a26