@article{GDZPPN002059886,
title = {Zur St\"orungstheorie linearer Operatoren in Banachr\"aumen.},
journal = {Commentarii mathematici Helvetici},
volume = {45},
year = {1970},
pages = {229-235},
zbl = {0188.44501},
url = {http://dml.mathdoc.fr/item/GDZPPN002059886}
}
Hess, Peter. Zur Störungstheorie linearer Operatoren in Banachräumen.. Commentarii mathematici Helvetici, Tome 45 (1970) pp. 229-235. http://gdmltest.u-ga.fr/item/GDZPPN002059886/