TY  - JOUR
AU  - E. P. Dolzhenko
AU  - V. I. Danchenko
TI  - Dependence of the differentiability of functions of several variables on their rate of approximation by rational functions
JO  - Izvestiya. Mathematics 
PY  - 1977
SP  - 171
EP  - 192
VL  - 11
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM2_1977_11_1_a5/
LA  - en
ID  - IM2_1977_11_1_a5
ER  -