SCHMIDT, A. L. On the Approximation of Quaternions. MATHEMATICA SCANDINAVICA, [S. l.], v. 34, p. 184–186, 1974. DOI: 10.7146/math.scand.a-11519. Disponível em: https://www.mscand.dk/article/view/11519. Acesso em: 29 apr. 2024.