EIDERMAN, Vladimir; ESSÉN, Matts. On Exceptional Sets for Superharmonic Functions in a Halfspace: An Inverse Problem. Mathematica Scandinavica, Berkeley, CA, United States, v. 76, p. 273–288, 1995. DOI: 10.7146/math.scand.a-12542. Disponível em: https://journals.msp.org/mscand/article/view/1085. Acesso em: 25 jul. 2026.