TY  - JOUR
AU  - N. M. Isakov
TI  - $C^r$-property and approximately differentiable functions
JO  - Matematičeskie zametki
PY  - 1991
SP  - 59
EP  - 62
VL  - 49
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MZM_1991_49_6_a6/
LA  - ru
ID  - MZM_1991_49_6_a6
ER  -