On 3-parameter families of piecewise smooth vector fields in the plane
  This paper is concerned with the local bifurcation analysis around typical singularities of piecewise smooth planar dynamical systems. Three-parameter families of a class of non$-$smooth vector fields are studied and the tridimensional bifurcation diagrams are exhibited. Our main results describe the unfolding of the so called fold-cusp singularity by means of the variation of 3 parameters. 
Claudio A. Buzzi, Tiago A. Carvalho, Marco A. Teixeira
math.DS