TY  - JOUR
AU  - V. A. Kozlov
AU  - V. A. Kondrat'ev
AU  - V. G. Maz'ya
TI  - On sign variation and the absence of ``strong'' zeros of solutions of elliptic equations
JO  - Izvestiya. Mathematics 
PY  - 1990
SP  - 337
EP  - 353
VL  - 34
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM2_1990_34_2_a5/
LA  - en
ID  - IM2_1990_34_2_a5
ER  -