HELSØ, Martin; RANESTAD, Kristian. Rational quartic spectrahedra. Mathematica Scandinavica, Berkeley, CA, United States, v. 127, n. 1, p. 79–99, 2021. DOI: 10.7146/math.scand.a-121456. Disponível em: https://journals.msp.org/mscand/article/view/165. Acesso em: 24 jul. 2026.