TY  - JOUR
AU  - I. V. Skrypnik
TI  - A condition for the regularity of a boundary point for a
JO  - Doklady Akademii Nauk
PY  - 1991
SP  - 821
EP  - 824
VL  - 320
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1991_320_4_a10/
LA  - ru
ID  - DAN_1991_320_4_a10
ER  -