Applied Mathematics Letters 18 (2005) 721728 www.elsevier.com/locate/aml Summary: Applied Mathematics Letters 18 (2005) 721­728 www.elsevier.com/locate/aml Nondifferentiable second order symmetric duality in multiobjective programming I. Ahmad, Z. Husain Department of Mathematics, Aligarh Muslim University, Aligarh-202 002, India Received 21 April 2004; accepted 3 May 2004 Abstract A pair of Mond­Weir type nondifferentiablemultiobjective second order symmetric dual programs is formulated and symmetric duality theorems are established under the assumptions of second order F-pseudoconvexity/ F-pseudoconcavity. © 2005 Elsevier Ltd. All rights reserved. Keywords: Symmetric duality; Multiobjective programming; Second order F-pseudoconvexity; Efficient solutions 1. Introduction Symmetric duality in mathematical programming was introduced by Dorn [8], who defined a program and its dual to be symmetric if the dual of the dual is the original problem. Chandra and Husain [5] studied a pair of symmetric dual nondifferentiable programs by assuming convexity/concavity of the scalar function f (x, y). Subsequently, Chandra et al. [3] presented another pair of symmetric dual nondifferentiable programs weakening convexity/concavity assumptions to pseudoconvexity/pseudoconcavity. Collections: Mathematics