Some fixed/coincidence point theorems under (ψ,φ)-contractivity conditions without an underlying metric structure

Antonio-Francisco Roldán-López-de-Hierro, Naseer Shahzad
2014 Fixed Point Theory and Applications  
In this paper we prove a coincidence point result in a space which does not have to satisfy any of the classical axioms that define a metric space. Furthermore, the ambient space need not be ordered and does not have to be complete. Then, this result may be applied in a wide range of different settings (metric spaces, quasi-metric spaces, pseudo-metric spaces, semi-metric spaces, pseudo-quasi-metric spaces, partial metric spaces, G-spaces, etc.). Finally, we illustrate how this result clarifies
more » ... is result clarifies and improves some well-known, recent results on this topic.
doi:10.1186/1687-1812-2014-218 fatcat:tccv7o3whnd3ledl3tkbq6z3em