Tripled fixed point theorems for monotone mappings in partially ordered metric spaces

In this paper, we introduce the concept of tripled fixed point for nonlinear and monotone mappings in partially ordered complete metric spaces and obtain existence as well as existence and uniqueness theorems for contractive type mappings. Our results generalize and extend recent tripled fixed point theorems established by Berinde and Borcut [Berinde, V., Borcut, M., Tripled fixed point theorems for contractive type mappings in partially ordered metric spaces. Nonlinear Anal. 74 (2011) 4889–4897]. Examples to support our new results are given.