GOODMAN, G. S.; YORKE, J. A. Misbehaviour of Solutions of the Differential Equation $y’=f(x,y)+\varepsilon$ when the Right Hand Side is Discontinuous. Mathematica Scandinavica, Berkeley, CA, United States, v. 27, p. 72–76, 1970. DOI: 10.7146/math.scand.a-10988. Disponível em: https://journals.msp.org/mscand/article/view/2337. Acesso em: 25 jul. 2026.