Piecewise linear differential systems without equilibria produce limit cycles?

On the birth of limit cycles for non-smooth dynamical systems

(2015) Jaume Llibre et al.   BULLETIN DES SCIENCES MATHEMATIQUES

On the number of limit cycles in discontinuous piecewise linear differential systems with two pieces separated by a straight line

(2015) Rodrigo D. Euzébio et al.   JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS

Maximum number of limit cycles for certain piecewise linear dynamical systems

(2015) Jaume Llibre et al.   NONLINEAR DYNAMICS

A general mechanism to generate three limit cycles in planar Filippov systems with two zones

(2014) Emilio Freire et al.   NONLINEAR DYNAMICS

The discontinuous matching of two planar linear foci can have three nested crossing limit cycles

(2014) E. Freire et al.   PUBLICACIONS MATEMATIQUES

Piecewise linear perturbations of a linear center

(2013) Claudio Buzzi et al.   DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS

On the number of limit cycles in general planar piecewise linear systems of node–node types

(2013) Song-Mei Huan et al.   JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS

Piecewise linear differential systems with two real saddles

(2013) Joan C. Artés et al.   MATHEMATICS AND COMPUTERS IN SIMULATION

Existence of limit cycles in general planar piecewise linear systems of saddle–saddle dynamics

(2013) Song-Mei Huan et al.   NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS

Limit cycles in a family of discontinuous piecewise linear differential systems with two zones in the plane

(2013) Denis de Carvalho Braga et al.   NONLINEAR DYNAMICS

On the number of limit cycles in general planar piecewise linear systems

(2012) Song-Mei Huan et al.   DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS

Dynamics and bifurcations of nonsmooth systems: A survey

(2012) Oleg Makarenkov et al.   PHYSICA D-NONLINEAR PHENOMENA

Canonical Discontinuous Planar Piecewise Linear Systems

(2012) Emilio Freire et al.   SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS

On Hopf bifurcation in non-smooth planar systems

(2009) Maoan Han et al.   JOURNAL OF DIFFERENTIAL EQUATIONS