BORYS, Clemens. A groupoid picture of the Elek algebras. Mathematica Scandinavica, Berkeley, CA, United States, v. 127, n. 2, p. 185–208, 2021. DOI: 10.7146/math.scand.a-122419. Disponível em: https://journals.msp.org/mscand/article/view/156. Acesso em: 24 jul. 2026.