Comments on “Design of sliding mode controller for a class of fractional-order chaotic systems” [Commun Nonlinear Sci Numer Simulat 17 (2012) 356–366]

Some comments on the paper [Yin C, Zhong S-M, Chen W-F. Design of sliding mode controller for a class of fractional-order chaotic systems. Commun Nonlinear Sci Numer Simulat 17 (2012) 356–366] are pointed out in this note. Besides, recently introduced fractional-order Lyapunov stability theorems are used to prove the finite-time occurrence of the sliding motion.