TY  - JOUR
AU  - V. I. Burenkov
TI  - The density of infinitely differentiable functions in Sobolev spaces for an arbitrary open set
JO  - Informatics and Automation
PY  - 1974
SP  - 39
EP  - 50
VL  - 131
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/TRSPY_1974_131_a4/
LA  - ru
ID  - TRSPY_1974_131_a4
ER  -