%0 Journal Article %A V. A. Petrovsky %T On the nature of zonal structure of crystals %J Doklady Akademii Nauk %D 1981 %P 630-633 %V 260 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1981_260_3_a27/ %G ru %F DAN_1981_260_3_a27