TY  - JOUR
AU  - V. K. Polishchuk
TI  - On the analytic theory of the equation $z^2u^{''}-f(z)u=0$.~I, II
JO  - Differencialʹnye uravneniâ
PY  - 1972
SP  - 1999
EP  - 2011
VL  - 8
IS  - 11
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1972_8_11_a11/
LA  - ru
ID  - DE_1972_8_11_a11
ER  -