TY  - JOUR
AU  - A. K. Kushpel'
TI  - Sharp estimates of the widths of convolution classes in the space $C_{2\pi}$
JO  - Informatics and Automation
PY  - 1987
SP  - 148
EP  - 149
VL  - 180
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/TRSPY_1987_180_a86/
LA  - ru
ID  - TRSPY_1987_180_a86
ER  -