SEPPÄLÄ, Mika; SORVALI, Tuomas. Traces of commutators of Möbius transformations. MATHEMATICA SCANDINAVICA, [S. l.], v. 68, p. 53–58, 1991. DOI: 10.7146/math.scand.a-12345. Disponível em: https://tidsskrift.dk/math/article/view/12345. Acesso em: 14 aug. 2026.