%0 Journal Article %A E. K. Ershov %T On structurally stable polynomial diffeomorphisms of the unit circle %J Differencialʹnye uravneniâ %D 1988 %P 687-689 %V 24 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1988_24_4_a18/ %G ru %F DE_1988_24_4_a18