A second-order dual to a nonlinear programming problem is formulated. This
dual uses the Fritz John necessary optimality conditions instead of the Kar
ush-Kuhn-Tucker necessary optimality conditions, and thus, does not require
a constraint qualification. Weak, strong, strict-converse, and converse du
ality theorems between primal and dual problems are established. (C) 2001 E
lsevier Science Ltd. All rights reserved.