### Some results on the stability of σeap(:) and σeδ(:) of linear relations

#### Abstract

conditions for the algebraic sum to become a closed and closable linear

relation. Secondly, we investigate the stability of the essential approximate

point spectrum σeap(:) as well as the essential defect spectrum σeδ(T ), in

terms of linear relations on Banach spaces, which were introduced by T.

Àlvarez and all in [1].

#### Full Text:

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