TY  - JOUR
AU  - D. P. Kostomarov
TI  - On boundary problems for eigen-values and characteristic functions of ordinary differential equations 

JO  - Doklady Akademii Nauk
PY  - 1957
SP  - 230
EP  - 233
VL  - 115
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1957_115_2_a7/
LA  - ru
ID  - DAN_1957_115_2_a7
ER  -