Co-ordinated σ-convex function and related integral inequalities.
An advanced class of convexity has been introduced in this article,
named as co-ordinated σ-convexity. This variant holds some other types
of two variable convex functions on co-ordinates as it’s special cases.
We also constituted integral inequalities enmeshed with the
Hermite-Hadamard type for co-ordinated σ-convex functions, as an