%0 Journal Article %A I. N. Belousov %A M. S. Nirova %T International conference “Algebra, Number Theory, and Mathematical Modeling of Dynamic Systems” devoted to the occasion of 70th birthday of A. Kh. Zhurtov %J Trudy Instituta matematiki i mehaniki %D 2019 %P 283-287 %V 25 %N 4 %U http://geodesic.mathdoc.fr/item/TIMM_2019_25_4_a29/ %G ru %F TIMM_2019_25_4_a29