GARDINER, Stephen J. Maximum principles for subharmonic functions. Mathematica Scandinavica, Berkeley, CA, United States, v. 68, p. 210–220, 1991. DOI: 10.7146/math.scand.a-12358. Disponível em: https://journals.msp.org/mscand/article/view/1273. Acesso em: 24 jul. 2026.