FOATA, D.; SCHÜTZENBERGER, M. P. On the Principle of Equivalence of Sparre Andersen. Mathematica Scandinavica, Berkeley, CA, United States, v. 28, p. 308–316, 1971. DOI: 10.7146/math.scand.a-11025. Disponível em: https://journals.msp.org/mscand/article/view/2272. Acesso em: 25 jul. 2026.