In this paper we consider some extended eigenvalue problems for some quasinormal operators. The spectrum of an algebra homomorphism defined by a compact normal operator is also investigated.
SERTBAŞ, MELTEM and YILMAZ, FATİH
"On the extended spectrum of some quasinormal operators,"
Turkish Journal of Mathematics: Vol. 41:
6, Article 10.
Available at: https://journals.tubitak.gov.tr/math/vol41/iss6/10