HUSTAD, Otte. Upper Semi-Continuity of Convex Functions and Openness of Affine Maps. MATHEMATICA SCANDINAVICA, [S. l.], v. 70, p. 43–77, 1992. DOI: 10.7146/math.scand.a-12386. Disponível em: https://tidsskrift.dk/math/article/view/12386. Acesso em: 13 aug. 2026.