A new concept of the c-distance in cone metric space has been introduced recently in 2011. The aim of this paper is to extend and generalize some coupled fixed-point theorems on c-distance in cone metric space. Some examples are given.
"Coupled Fixed Point Theorems of Single-Valued Mapping for c-Distance in Cone Metric Spaces." J. Appl. Math. 2012 1 - 20, 2012. https://doi.org/10.1155/2012/246516