STOUT, Edgar Lee. Algebras on Surfaces. Mathematica Scandinavica, Berkeley, CA, United States, v. 116, n. 1, p. 104–125, 2015. DOI: 10.7146/math.scand.a-20453. Disponível em: https://journals.msp.org/mscand/article/view/397. Acesso em: 24 jul. 2026.