YAMAGUCHI, Hiroshi. An extension of a theorem of F. Forelli. Mathematica Scandinavica, Berkeley, CA, United States, v. 52, p. 145–160, 1983. DOI: 10.7146/math.scand.a-12000. Disponível em: https://journals.msp.org/mscand/article/view/1621. Acesso em: 25 jul. 2026.