“…Constraint qualifications involving epigraphs have been studied and extensively used by Jeyakumar and his collaborators in [11,12,23,28,29,30,31], Boţ et al [4,5,6,9,10], Dinh et al [16,17,19,20,21,22], and Li et al [40,41]. Our main aims in the present paper is to use these constraint qualifications (or their variations) to provide complete characterizations for the Farkas rule and the stable Farkas rule, and for the (strong/strong stable ) Lagrangian duality.…”