in this paper, we give a new fixed point theorem forweakly quasi-contraction maps in metric spaces. our results extend and improve some fixed point and theorems in literature.

A well-quasi-order is an order which contains no infinite decreasing sequence and no infinite collection of incomparable elements. In this paper, we consider graph classes defined by excluding one graph as contraction. More precisely, we give a complete characterization of graphs H such that the class of H-contraction-free graphs is well-quasi-ordered by the contraction relation. This result is...

In this note, we establish and improve some results on fixed point theory in topological vector spaces. As a generalization of contraction maps, the concept of quasi contraction multivalued maps on a topological vector space will be defined. Further, it is shown that a quasi contraction and closed multivalued map on a topological vector space has a unique fixed point if it is bounded value.

In 2009, Ilić and Rakoc̆ević proved that quasi-contraction maps on normal cone metric spaces have a unique fixed point (Ilić and Rakoc̆ević, 2009 [6]). Then, Kadelburg, Radenović and Rakoc̆ević generalized their results by considering an additional assumption (Kadelburg et al., 2009 [7]). Also, they proved that quasi-contraction maps on cone metric spaces have the property (P) whenever λ ∈ (0, 2 )...

In this paper, we introduce the concepts of qpb-cyclic-Banach contraction mapping, qpb-cyclic-Kannan mapping and qpb-cyclic β-quasi-contraction mapping and establish the existence and uniqueness of fixed point theorems for these mappings in quasi-partial b-metric spaces. Some examples are presented to validate our results. c ©2016 All rights reserved.

In this work, we give a partial positive answer to the question concerning set-valued quasicontraction proposed by Amini-Harandi (Appl. Math. Lett. 24:1791-1794 2011). By useful lemma, prove fixed point theorem for quasi-contraction, which extends range of contraction constant in result from [0, 1/2) 1/3? 3). Also, new simple proof quasi-contraction type Haghi et al. 25:843-846 2012). Finally, ...