TY  - JOUR
AU  - D. A. Popov
TI  - The discrete spectrum of the Laplace operator on the fundamental domain of the modular group and the Chebyshev psi-function
JO  - Izvestiya. Mathematics 
PY  - 2019
SP  - 1066
EP  - 1079
VL  - 83
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM2_2019_83_5_a6/
LA  - en
ID  - IM2_2019_83_5_a6
ER  -