Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{CMH_1970__45_139435, author = {Peter Hess}, title = {Zur {St\"orungstheorie} linearer {Operatoren} in {Banachr\"aumen.}}, journal = {Commentarii mathematici Helvetici}, pages = {229--235}, publisher = {mathdoc}, volume = {45}, year = {1970}, zbl = {0188.44501}, url = {http://geodesic.mathdoc.fr/item/CMH_1970__45_139435/} }
Peter Hess. Zur Störungstheorie linearer Operatoren in Banachräumen.. Commentarii mathematici Helvetici, Tome 45 (1970), pp. 229-235. http://geodesic.mathdoc.fr/item/CMH_1970__45_139435/