PEDERSEN, Gert Kjaergaard. The Structure Space of a Left Ideal. Mathematica Scandinavica, Berkeley, CA, United States, v. 14, p. 90–92, 1964. DOI: 10.7146/math.scand.a-10708. Disponível em: https://journals.msp.org/mscand/article/view/2598. Acesso em: 25 jul. 2026.