000
00272nam a2200109 4500
008
160616s 000 0
245
_a
Perturbation of spectra in hilbert space
100
_a
Friedrichs, K.O
500
_a
B313N K52
942
_c
BK
_2
BK4755
080
_a
513.882 FRI
999
_c
4755
_d
4755