CARVALHO, F. J. C. De; ROBERTSON, S. A. Self-parallel curves. Mathematica Scandinavica, Berkeley, CA, United States, v. 65, p. 67–74, 1989. DOI: 10.7146/math.scand.a-12266. Disponível em: https://journals.msp.org/mscand/article/view/1377. Acesso em: 25 jul. 2026.