Symmetric duality involving invexity in multiobjective fractional programming

A pair of symmetric dual multiobjective fractional programming problems are considered where the same set of multipliers are taken corresponding to the various objectives in both the problems and the duality results are proved under invexity conditions. Duality theorems are also given for another pair of symmetric dual fractional programming problems having different set of multipliers corresponding the various objectives in both the problems. A self duality theorem is also established for either of the pairs of the symmetric dual programs.