%0 Journal Article %A A. M. Kamachkin %T Existence and uniqueness of the periodic solution of a relay system with hysteresis %J Differencialʹnye uravneniâ %D 1972 %P 1505-1506 %V 8 %N 8 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1972_8_8_a22/ %G ru %F DE_1972_8_8_a22