TY  - JOUR
AU  - H. Brezis
TI  - How to recognize constant functions. Connections with Sobolev spaces
JO  - Trudy Matematicheskogo Instituta imeni V.A. Steklova
PY  - 2002
SP  - 693
EP  - 708
VL  - 57
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/RM_2002_57_4_a1/
LA  - en
ID  - RM_2002_57_4_a1
ER  -