LANDSTAD, M. B. Algebras of spherical functions associated with covariant systems over a compact group. MATHEMATICA SCANDINAVICA, [S. l.], v. 47, p. 137–149, 1980. DOI: 10.7146/math.scand.a-11880. Disponível em: https://www.mscand.dk/article/view/11880. Acesso em: 5 may. 2024.