TY  - JOUR
TI  - Meetings of the St.~Petersburg Mathematical Society
JO  - Trudy Matematicheskogo Instituta imeni V.A. Steklova
PY  - 2009
SP  - 577
EP  - 582
VL  - 64
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/RM_2009_64_3_a8/
LA  - en
ID  - RM_2009_64_3_a8
ER  -