MAUGESTEN, Paul Aleksander; MOE, Torgunn Karoline. The $2$-Hessian and sextactic points on plane algebraic curves. Mathematica Scandinavica, Berkeley, CA, United States, v. 125, n. 1, p. 13–38, 2019. DOI: 10.7146/math.scand.a-114715. Disponível em: https://journals.msp.org/mscand/article/view/226. Acesso em: 24 jul. 2026.