TY  - JOUR
AU  - V. V. Golovchanskii
AU  - M. N. Smotrov
TI  - On the spectrum of the Laplace--Beltrami operator for congruence subgroups of the modular group
JO  - Algebra i analiz
PY  - 2011
SP  - 31
EP  - 39
VL  - 23
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/AA_2011_23_4_a1/
LA  - ru
ID  - AA_2011_23_4_a1
ER  -