WERNER, D. The Perfekt theory of $M$-ideals. MATHEMATICA SCANDINAVICA, [S. l.], v. 128, n. 2, 2022. DOI: 10.7146/math.scand.a-132230. Disponível em: https://www.mscand.dk/article/view/132230. Acesso em: 11 apr. 2025.