A generalization of vectorial equilibria. - Qamrul Hasan Ansari; Werner Oettli; Dirk Schläger (Math. Methods Oper. Res., 1997)

Conjugate Functions for Convex and Nonconvex Duality. - Werner Oettli; Dirk Schläger (J. Glob. Optim., 1998)

Existence of equilibria for monotone multivalued mappings. - Werner Oettli; Dirk Schläger (Math. Methods Oper. Res., 1998)