TY  - JOUR
AU  - A. S. Markus
TI  - The root-vector expansion of a weakly perturbed self-adjoint operator
JO  - Doklady Akademii Nauk
PY  - 1962
SP  - 538
EP  - 541
VL  - 142
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1962_142_3_a9/
LA  - ru
ID  - DAN_1962_142_3_a9
ER  -