The well-known Banach’s fixed point theorem asserts that ifD X, f is contractive and X, d is complete, then f has a unique fixed point inX. It is well known that the Banach contraction principle 1 is a very useful and classical tool in nonlinear analysis. In 1969, Boyd and Wong 2 introduced the notion ofΦ-contraction. A mapping f : X → X on a metric space is called Φ-contraction if there exists...

In this paper, we shall generalize the definition of (φ− k) −B contraction to multi-valued mappings which was presented before in single valued case by Mihet. Then we shall prove two fixed point theorems for multi-valued (φ− k) − B contraction mappings in probabilistic metric space.

We correct the proof of Theorem 6 in the letter ‘‘Fixed point theory for cyclic weak φ-contraction’’ [E. Karapınar, Fixed point theory for cyclic weak φ-contraction, Appl. Math. Lett. 24 (6) (2011) 822–825]. © 2010 Elsevier Ltd. All rights reserved.

Dynamic doxastic logic concerns an agent who inhabits a world and is able to form theories about it. In particular there are three types of doxastic action of which he is capable: expanding his beliefs by accepting a proposition φ without modifying the resulting set of beliefs; revising his beliefs by accepting a proposition φ and modifying the resulting set of beliefs; and contracting his beli...

Branciari [1] obtained a fixed point result for a single mapping satisfying an analogue of Banach’s contraction principle for an integral-type inequality. The second author [3] proved two fixed point theorems involving more general contractive conditions. In this paper, we establish a general principle, which makes it possible to prove many fixed point theorems for a pair of maps of integral ty...

Jachymski [ Proc. Amer. Math. Soc., 136 (2008), 1359-1373] gave modified version of a Banach fixed point theorem on a metric space endowed with a graph. In the present paper, (G, Φ)-graphic contractions have been de ned by using a comparison function and studied the existence of fixed points. Also, Hardy-Rogers G-contraction have been introduced and some fixed point theorems have been proved. S...

Abstract In this paper, using the notion of w -distance in metric spaces, we introduce two types nonlinear contractions, $(\iota ,\psi ,\varphi ,\phi ,p)$ ( ι , ψ φ ϕ p ) and rational- , \var...