ACAR, ÖZLEM; Altun, Ishak; Romaguera Bonilla, Salvador("Babeş-Bolyai" University of Cluj-Napoca, 2013)

[EN] We introduce a new type of Caristi's mapping on partial metric spaces and show that a partial metric space is complete if and only if every Caristi mapping has a fixed point. From this result we deduce a characterization ...

Altun, Ishak; Romaguera Bonilla, Salvador(University of Belgrade and Academic Mind, 2012)

We characterize both complete and 0-complete partial metri
c spaces in terms
of weakly contractive mappings having a fixed point. Our resu
lts extend
a well-known characterization of metric completeness due ...

In the present paper, considering a new concept of multivalued almost F-contraction, we give
a general class of multivalued weakly Picard operators on complete metric spaces. Also, we give some
illustrative examples ...

Altun, Ishak; Durmaz, Gonca(Universitat Politècnica de València, 2012-10-01)

[EN] The concept of partial metric p on a nonempty set X was introduced by Matthews. One of the most interesting properties of a partial metric is that p(x, x) may not be zero for x e X. Also, each partial metric p on a ...