TY  - JOUR
AU  - G. V. Radzievskii
TI  - Direct and converse theorems in problems of approximation by vectors of finite degree
JO  - Sbornik. Mathematics
PY  - 1998
SP  - 561
EP  - 601
VL  - 189
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/SM_1998_189_4_a3/
LA  - en
ID  - SM_1998_189_4_a3
ER  -