UPMEIER, H. Derivatons of Jordan $C^*$-algebras. MATHEMATICA SCANDINAVICA, [S. l.], v. 46, p. 251–264, 1980. DOI: 10.7146/math.scand.a-11867. Disponível em: https://www.mscand.dk/article/view/11867. Acesso em: 5 may. 2024.