LIU, Teng-sun; WANG, Ju-kwei. Sums and Intersections of Lebesgue Spaces. Mathematica Scandinavica, Berkeley, CA, United States, v. 23, p. 241–251, 1968. DOI: 10.7146/math.scand.a-10916. Disponível em: https://journals.msp.org/mscand/article/view/2437. Acesso em: 25 jul. 2026.