ZOWE, Jochem. Subdifferentiability of Convex Functions with Values in an Ordered Vector Space. Mathematica Scandinavica, Berkeley, CA, United States, v. 34, p. 69–83, 1974. DOI: 10.7146/math.scand.a-11507. Disponível em: https://journals.msp.org/mscand/article/view/2140. Acesso em: 25 jul. 2026.