PLEIJEL, Arne. Beiträge zur Theorie der Laplace-Stieltjes -Transformationen. Mathematica Scandinavica, Berkeley, CA, United States, v. 4, p. 147–152, 1956. DOI: 10.7146/math.scand.a-10464. Disponível em: https://journals.msp.org/mscand/article/view/2862. Acesso em: 25 jul. 2026.