%0 Journal Article %A A. A. Davydov %T Singularities of the admissibility boundary in two-dimensional control systems %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 1982 %P 200-201 %V 37 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/RM_1982_37_3_a7/ %G en %F RM_1982_37_3_a7