%0 Journal Article %A Ant. A. Klyachko %A A. M. Mazhuga %T Verbally closed virtually free subgroups %J Sbornik. Mathematics %D 2018 %P 850-856 %V 209 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/SM_2018_209_6_a4/ %G en %F SM_2018_209_6_a4