An algorithm for computing an element of the Clarke generalized Jacobian   of a difference of max-type functions
  We show that the algorithm for computing an element of the Clarke generalized Jacobian of a max-type function proposed by Zheng-da Huang and Guo-chun Ma can be extended to a much wider class of functions representable as a difference of max-type functions. 
Ana Horta and Vera Roshchina
math.OC