On conjugations for functions with values in extensions of ordered groups

We continue our study of generalized conjugations for functions with values in the canonical enlargement of a complete ordered group, started in [10], which encompass various kinds of known conjugations and polarities. We obtain extensions, to this framework, of some results on d.c. duality theory and subdifferentials, and we give some applications to conjugations and subdifferentials for functions with values in R+̄ = [0, +∞]. © 1997 Kluwer Academic Publishers.