A class of nonconvex functions and mathematical programming
Terence Weir, V. Jeyakumar · Bulletin of the Australian Mathematical Society · 1988
A class of functions, called pre-invex, is defined. These functions are more general than convex functions and when differentiable are invex. Optimality conditions and duality theorems are given for both scalar-valued and vector-valued programs involving pre-invex functions.