2D discrete mapping

Does anyone know relevant literature of the following 2D discrete system:

x_n+1 = a x_n + b y_n + c sgn(x_n)

y_n+1 = x_n

Here a,b and c are parameters and sgn is the sign operator.

TIA Maarten

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Maarten van Reeuwijk dept. of Multiscale Physics
Phd student Faculty of Applied Sciences
maarten.ws.tn.tudelft.nl Delft University of Technology
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