Some fixed point theorems in terms of two measures of noncompactness


In this paper several fixed point theorems of Sadovskii type are obtained for operators on spaces endowed with two norms and two corresponding measures of noncompactness. An application to Hammerstein integral equations in a Banach space is included to illustrate the theory.


Radu Precup
Department of Mathematics Babes-Bolyai University, Cluj-Napoca, Romania

Ioan A. Rus
Babes-Bolyai University, Department of Mathematics, Cluj-Napoca, Romania


Linear space with two norms; measure of noncompactness; condensing operator; fixed point; radial retraction; retractible operator; integral equation.

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R. Precup, I.A. Rus,  Some fixed point theorems in terms of two measures of noncompactness, Mathematica 56 (79) (2014) no 2, 158-165.


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