TY  - JOUR
AU  - V. Yu. Popov
TI  - Exact constants in Jackson inequalities for best spherical mean square approximations
JO  - Izvestiâ vysših učebnyh zavedenij. Matematika
PY  - 1981
SP  - 67
EP  - 78
IS  - 12
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IVM_1981_12_a9/
LA  - ru
ID  - IVM_1981_12_a9
ER  -